Codes and Trans "jumping out of gear"

Thanks for the peace of mind for my sanity SigEp. I re-read everything in the tech articles again and then I cam to the same conclusion you said about the codes. Sometimes thebiggest help about a forum is just writing your thoughts out and re-reading them. Helps you catch yourself. I will look into the test procedures for the MLPS and run outside and do them later this evening.

Sackman - I wasnt towing anything. When it "jumped" out of overdrive, once it settled back down, it was in OD again and the cruise never deactivated. I thought if the brake was triggered the cuise died???? BUT... your thought is interesting because my trailer hookup wiring has been absolutely ABUSED. the box is actually hanging by a "thread of a bolt". I will immediately eliminate this though. You've given me reason enough to address this sore spot on my rig.

One thing leading me to the MLPS is the fact that the only common denominator in all the times this symptom has occured is the fact that it has rained within the past 24 hours of every occurence. I will test this... any advice on the MLPS other than the standard tests? How much $$$?

OK guys. I've searched, and come up a little short. If you'll notice in the previous post, I replaced the MLPS and my problems went completely away, or at least I thought. Just completed a couple of round trips.

First, right after the MLPS replacement, I went from Charlotte to Atlanta (little over 500 miles RT), and had zero issues withthe tranny.

Drove the following week about 100 miles roundtrip to the Charlotte pull a part and did great on the way there. Ran AC and it was REALLY hot that day. Was in pull a part for about an hour. When I came outside, loaded, the truck and cranked it, the engine had a stumble at idle. Ive noticed this several times, when the AC has been on, and when I crank with the AC on after driving a long distance and then restarting the truck. Not sure if this is related to the trans issue, but they seem to happen together. When I pulled out of the parking lot, the transmission performed the 1-2 shift in lmp mode. 2-3 was in limp as well, and the rpms went up with the throttle pressure, like the trans was slipping. Was in traffic, so I couldn't stop. Pulled up to a light, sat for 45 seconds, and made a u turn. Tranny shifted fine with no slip and I drove the remaining 50 miles home with no issues. When it was slipping, if I pressed the throttle the rpms would go up 1k or so ( i didnt push it any harder than this for fear of damage to trans).

Lastly, I went to Richmond VA on business this week. 650 miles round trip. The entire way up there, everything was fine. On the way back, the first 150 miles was fine. Stopped for dinner and was in and out really quick. Got back in the truck, and started it, and the engine was idling rough again. Pulled out onto the road and I hard the limp mode and slipping again. Drove to a gas station and when I started it back up at gas station, it didn't appear to be running rough. Started down the interstate and did fine cruising at 70mph with cruise control on for about 5 minutes. Suddenly, I hit a small bump (not sure if this is related) and the truck fell flat on its face. The cruise was turned off, and when I got on the throttle manually, the slipping occured again. All I could do was about 55-60 mph, the entire while the rpms were slipping about 500 or so above where they would normally be at the same speed. This was with maybe 1/8th throttle. If I gave it more throttle, the slipping would get worse. So, I limped it off to the emergency lane, emergency flashers and all. Stopped the truck and turned off the ignition. Let it sit for less than a minute, cranked it and pulled back onto the interstate. The truck behaved ABSOLUTELY NORMAL the rest of the way home (160 ish miles) at 70+ mph. There wasn't even a hint of a missed/hard shift or slipping.

It dawned on me a few miles into the trip to try to recreate the issue. It seemed the trans was not slipping, but rather the Torque Converter was ( I am by no means remotely familiar with an auto trans, other than what I've read. In fact, at 32 years old, I've had a dozen or so vehicles and this is the first auto). So, I was thinking, what could cause both the trans (or torque converter) to slip and the cruise to deactivate. BRAKES! So my test was.... Rolling down the road at 65mph, I lightly held pressure on the brake pedal and pressed the throttle. There it was! the rpms climbed and the truck maintianed its original speed. Here's the kicker though, when the cruise deactivated when the truck slipped on its own after hitting the bump, I'm FAIRLY CERTAIN the cruise completely deactivated, meaning I had to turn it back on at the on/off setting on the left of the steering wheel. In other words, I couldn't simply hit "Resume" , but rather, I had to turn the system back on first. Normally when brakes are applied, it simply turns the cruise off, but the cruise system is still enabled, so you can simply hit resume. Like I said, I'm not 100% certain it happened this way, as I was busy trying not to get hit ny other cars that were doing 20+ mph more than me while I was trying to make it to the shoulder.

So, I know it's a long post, but I was wondering if someone would have any inkling of the wiring for the brake system and at what sensor or citcuit, these symptoms could be caused through an interaction of the braking system, trans system and the cruise. Am I even on the right track?

Oh... and the last note.... My truck has never thrown any code other than system pass. The O/D light never blinked. It seems as though the tranny is absolutely fine. It's just getting mixed messages from other systems???!?!?!? I would think if the trans were at fault, it would have slipped the rest of the trip(s), instead of just once in the very middle of a long trip.

yo
Right pdabbs911;
could be brake light/Switch issue; intermittent, etc.

Brake On/Off (BOO) Switch 13480: The brake on/off switch tells the powertrain control module when the brakes are applied. The switch is closed when the brakes are applied and open when they are released. The PCM uses this signal to disengage torque converter clutch when brake is applied. Failed on or not connected — Torque converter clutch will not engage at less than 1/3 throttle. Failed off — Torque converter clutch will not disengage when brake is applied. DTC: 536, P1703. Source: by Ford via Steve83

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Multi-Function Switch (MFS), Hazard & Brake Light MAY Disengage E4OD Torque Converter Lock-up Discussion in 92-96
Source: by members at http://www.nloc.net/vbforum/gen-1-l...ts-disengage-torque-converter-lockup-how.html
Multi-Function Switch (MFS), Hazard & Brake Light MAY Disengage E4OD Torque Converter Lock-up; "...I was living with the torque converter unlocking with the R/H turn signal. And low and behold after I changed the L/H brake/turn signal bulb the torque converter stopped unlocking with the R/H turn signal. Don't ask me but it did fix it..."
Source: by Mike G & Miesk5 at Ford Bronco Zone Forums
There is also the CC Recall and field service Update at large; has this been done yet?
info in my site under ELECTRICAL > Cruise (Speed) Control
=========
Torque Converter Operation Test & Cutaway Depiction; "...If the shudder occurs a) during the 3-4 or 4-3 shift at HEAVY throttle, or b) at 40mph in 2, OD OFF, and OD, or c) at the same RPM in every gear, or d) coasting, cruising, or in R, or e) during extended light braking, then it is NOT TC clutch shudder; The following is a list of common vehicle concerns that have been misdiagnosed as torque converter clutch shudder. For diagnosis of the following items, refer to the appropriate sections of the workshop manual and the Powertrain Control/Emissions Diagnosis manual (PCED). Spark plugs - check for cracks, high resistance or broken insulators. Plug wires. Fuel injector - filter may be plugged. Fuel contamination - engine runs poorly. EGR valve - valve may let in too much exhaust gas and cause engine to run lean. Vacuum leak - engine will not get correct air/fuel mixture. MAP/MAF sensor - improper air/fuel mixture. HO2S sensor - too rich/lean air/fuel mixture. Fuel pressure - may be too low. Engine mounts -loose/damaged mounts can cause vibration concerns. Axle joints - check for vibration..."
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net

Torque Converter Shudder; "...If the shudder occurs
a) during the 3-4 or 4-3 shift at HEAVY throttle,
or b) at 40mph in 2, OD OFF, and OD, or c) at the same RPM in every gear,
or d) coasting, cruising, or in R, or e) during extended light braking,
then it is NOT TC clutch shudder;

The following is a list of common vehicle concerns that have been misdiagnosed as torque converter clutch shudder. For diagnosis of the following items, refer to the appropriate sections of the workshop manual and the Powertrain Control/Emissions Diagnosis manual (PCED).
Spark plugs - check for cracks, high resistance or broken insulators.
Plug wires.
Fuel injector - filter may be plugged.
Fuel contamination - engine runs poorly.
EGR valve - valve may let in too much exhaust gas and cause engine to run lean.
Vacuum leak - engine will not get correct air/fuel mixture.
MAP/MAF sensor - improper air/fuel mixture. HO2S sensor - too rich/lean air/fuel mixture.
Fuel pressure - may be too low.
Engine mounts -loose/damaged mounts can cause vibration concerns.
Axle joints - check for vibration..."
Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net

Ok.... For Sig.

No Codes

Trans seems to be slipping but I think its the torque converter (happens at any speed including 70+ mph)

Limp mode for shifts

Rough idle upon start up after a long drive on interstate, followed by limp mode (not sure if the two are related)

Pulled over on side of interstate, shut the truck off and started it back up less than 60 seconds later. No issues for the remaining 150 miles.

Was able to replicate the failure by lightly holding the brake while driving 60+ mph down the interstate. the trans (torque converter I think) would slip

When failure originally occured on the interstate, the cruise completely de-activated (I think - a lot was happening at the time) meaning I had to hit the "cruise on" activation button rather than "resume"

This all led me to believe that the trans is actually fine and another system is causing the interruption. I will read the info from Mike, but been unable to so far. I was wondering what circuits have interaction with the torque converter lockup.... brake switch on the pedal, pressure switch in front of the brake fluid reservoir, etc. All bulbs appear to be working fine. Hope that one was short enough.

yo
re; what circuits have interaction with the torque converter lockup.... brake switch on the pedal, pressure switch in front of the brake fluid reservoir, etc. All bulbs appear to be working fine.
Here's da skinny;
by Ford via Steve83


E4OD Controls & Solenoids

Powertrain Control Module (PCM) 12A650:
On vehicles equipped with gasoline engines, the operation of the E4OD automatic transmission is controlled by the powertrain control module. Many input sensors provide information to the powertrain control module, which then controls the actuators that affect transmission operation.
On vehicles equipped with diesel engines, the operation of the E4OD automatic transmission is also controlled by the powertrain control module. However, some of the input sensors are different.

Air Conditioning (A/C) Clutch 2884:
Description: The air conditioning clutch is an electromagnetic clutch that is energized when the clutch cycling A/C pressure cut-off switch closes. The A/C pressure cut-off switch is located on the suction accumulator-drier. The closing of the A/C pressure cut-off switch completes the circuit to the clutch and draws it into engagement with the compressor driveshaft. Used as an input to determine electronic pressure control when the air conditioning clutch is engaged to compensate for the additional load on the engine.
Symptoms: Failed on — electronic pressure control slightly low with A/C off. Failed off — electronic pressure control slightly high with A/C on.
Diagnostic Trouble Codes: 539, P1460, P1463, P1464.

Brake On/Off (BOO) Switch 13480:
Description: The brake on/off switch tells the powertrain control module when the brakes are applied. The switch is closed when the brakes are applied and open when they are released. The PCM uses this signal to disengage torque converter clutch when brake is applied.
Symptoms: Failed on or not connected — Torque converter clutch will not engage at less than 1/3 throttle. Failed off — Torque converter clutch will not disengage when brake is applied.
Diagnostic Trouble Codes: 536, P1703.

Distributor Ignition (DI) System:
Description: On gasoline engines, the profile ignition pickup sensor sends a signal to the powertrain control module indicating the engine rpm and the crankshaft position.
Symptoms: Engine will stall or miss.
Diagnostic Trouble Codes: 211, P0340, P0341, P0344.

Camshaft Position (CMP) Sensor — 7.3L DI Diesel Only:
Description: On the 7.3L DI diesel engines, the CMP sensor provides engine rpm information to the PCM. This rpm input is used to determine shift scheduling and EPC pressure.
Symptoms: No start.
Diagnostic Trouble Codes: P0340, P0341, P0344

4x4 Low (4x4L) Switch:
Description: The low range switch is located on the transfer case cover. It provides an indication of when the 4x4 transfer case gear system is in the LOW range. Modifies shift schedule for 4x4L transfer case gear ratio.
Symptoms: Failed on — Early shift schedule in 4x2 and 4x4H. Failed off — Shifts delayed in 4x4L. If the 4x4 low indicator light fuse is blown, the transmission will shift according to 4x4 low shift schedule regardless of transfer case position.
Diagnostic Trouble Codes: 633, 691, P1729, P1781.

Mass Air Flow (MAF) Sensor 12B579:
Description: The mass air flow sensor directly measures the mass of air flowing into the engine. The sensor output is a D.C. (analog) signal ranging from 0.5 volt to 5 volts used by the processor to calculate injector pulse width. Used as an input to determine electronic pressure control.
Symptoms: High electronic pressure, firm shifts and engagements.
Diagnostic Trouble Codes: 157, 158, 159, 184, 185, P0102, P0103, P1100, P1101.

Manifold Absolute Pressure (MAP) Sensor — Gasoline Engines:
Description: On gasoline engines, the manifold absolute pressure (MAP) sensor senses atmospheric pressure to produce an electrical signal. The frequency of this signal varies with intake manifold pressure. The powertrain control module monitors this signal to determine altitude. The PCM then adjusts the E4OD shift schedule and EPC pressure for altitude.
On diesel engines, the MAP sensor measures boost pressure. The PCM monitors this signal and adjusts EPC pressure.
Symptoms: Firm shift feel, late shifts at altitude.
Diagnostic Trouble Codes: 126-129, P0235-P0237.

Barometric Pressure (BARO) Sensor — 7.3L DI Diesel Only:
Description: The barometric pressure sensor operates similarly to the manifold absolute pressure sensor. It measures barometric pressure instead of intake manifold pressure. The powertrain control module uses the signal from the barometric pressure sensor to determine the altitude at which the vehicle is operating. The powertrain control module then adjusts the E4OD shift schedule and EPC pressure for the altitude.
Symptoms: Firm shift feel, late shifts at altitude.
Diagnostic Trouble Codes: P0107, P0108.

Programmable Speedometer/Odometer Module (PSOM):
Description: The programmable speedometer/odometer module receives input from the rear brake anti-lock sensor, which is mounted on the rear axle differential housing. The PSOM processes this input signal information and relays it to the powertrain control module and the speed control module. This signal tells the powertrain control module the vehicle speed in miles per hour (mph). Used as an input in determining shift scheduling and electronic pressure control.
Symptoms: Harsh engagements, firm shift feel, abnormal shift schedule, unexpected downshifts may occur at closed throttle, abnormal torque converter clutch operation or engages only at wide-open throttle (WOT). May flash transmission control indicator lamp.
Diagnostic Trouble Codes: 452, P0500, P1500, P1501, P0503.

Transmission Control Switch (TCS) and Transmission Control Indicator Lamp (TCIL):
Description: The transmission control switch (TCS) is a momentary contact switch. When the switch is pressed, a signal is sent to the powertrain control module. The powertrain control module then energizes the transmission control indicator lamp and the coast clutch solenoid, applying the coast clutch to provide engine braking and cancels fourth gear operation. The TCIL indicates overdrive cancel mode activated (lamp on), electronic pressure control circuit shorted or monitored sensor failure (lamp flashing).
Sensor: Transmission Control Switch.
Symptoms: No overdrive cancel when switch is cycled.
Diagnostic Trouble Codes:
DTC 632, Overdrive cancel switch did not change state during KOER; is possibly the result of the test being done incorrectly. When you do a KOER test, you need to cycle the switch on and off, if you did, Possible Causes:
Switch is damaged.
Shorted harness.
Damaged Powertrain Control Module (PCM).
Open harness or fuse.

P1780, tested during Key On Engine Off (KOEO) On-Board Diagnostic only.
Actuator: Transmission Control Indicator Lamp.
Symptoms: Failed on — overdrive cancel mode always indicated, no flashing for electronic pressure control circuit shorted. Failed off — overdrive cancel mode never indicated, no flashing for electronic pressure control circuit shorted, also may be due to a bad fuse. Erratic operation (flashing) may be due to a wiring concern.
Diagnostic Trouble Codes: 631, P1779.

Throttle Position (TP) Sensor 9B989:
Description: The throttle position sensor is a potentiometer that is mounted on the throttle body on gas applications and on the fuel injection pump lever on diesel applications. The throttle position sensor detects the position of the throttle plate or lever and sends this information as a voltage signal to the powertrain control module.
If a malfunction occurs in the throttle position sensor circuit, the powertrain control module will recognize that the throttle position sensor signal is out of specification. The powertrain control module will then operate the E4OD transmission at a higher line pressure to prevent transmission damage. This high line pressure causes harsh upshift and engagements. Used as an input to determine shift scheduling and electronic pressure control.
Symptoms: Harsh engagements, firm shift feel, abnormal shift schedule, abnormal or no torque converter clutch operation. May flash transmission control indicator lamp.
Diagnostic Trouble Codes: 121, 122, 123, 124, 125, 167, P0121, P0122, P0123, P1120, P1121, P1124, P1125.

Accelerator Pedal (AP) Sensor — 7.3L DI Diesel Only:
Description: The accelerator pedal (AP) sensor is mounted on the accelerator pedal on 7.3L DI diesel engines. The AP sensor detects the position of the accelerator pedal and sends this information as a voltage signal to the PCM.
If a malfunction occurs in the AP sensor circuit, the powertrain control module will recognize that the AP sensor signal is out of specification. The powertrain control module will then operate the E4OD transmission at a higher line pressure to prevent transmission damage. This high line pressure causes harsh upshift and engagements. Used as an input to determine shift scheduling and electronic pressure control.
Symptoms: Harsh engagements, firm shift feel, abnormal shift schedule, abnormal or no torque converter clutch operation. May flash transmission control indicator lamp.
Diagnostic Trouble Codes: 122, 123, P0122, P0123

Vehicle Speed Sensor (VSS) 9E731:
Description: The vehicle speed sensor is a variable reluctance sensor that sends an AC/frequency signal to the powertrain control module. The vehicle speed sensor signal is used by the powertrain control module to calculate vehicle speed in mph. Used as an input in determining shift scheduling and electronic pressure control.
Symptoms: Harsh engagements, firm shift feel, abnormal shift schedule; unexpected downshifts may occur at closed throttle, abnormal torque converter clutch operation or torque converter clutch engages only at wide-open throttle. May flash transmission control indicator lamp.
Diagnostic Trouble Codes: 452, P0500, P1500, P1501, P0503.

Transmission Fluid Temperature (TFT) Sensor:
Description: The transmission fluid temperature sensor is located on the solenoid body assembly in the transmission sump. It is a temperature-sensitive device called a thermistor. The resistance value of the transmission fluid temperature sensor will vary with temperature change. The powertrain control module monitors voltage across the transmission fluid temperature sensor to determine the temperature of the transmission fluid. The powertrain control module uses this signal to determine whether a cold start shift schedule is necessary. The cold start shift schedule lowers shift speeds to allow for the reduced performance of cold engine operation. The powertrain control module also uses the transmission fluid temperature sensor input to adjust electronic pressure control pressure for temperature effects and inhibit torque converter clutch operation during the warm-up period.
Symptoms: Torque converter clutch and stabilized shift schedule happens too soon after a cold start. Codes P1783 or 657 indicate transmission fluid temperature exceeds 132°C (270° F), results in increased EPC pressure and torque converter clutch engagement. May flash transmission control indicator lamp.
Diagnostic Trouble Codes: 636, 637, 638, 657, P0712, P0713, P1711, P1783.

Transmission Range (TR) Sensor 7A247:
Description: The powertrain control module sends voltage to the Transmission Range (TR) sensor. The TR sensor incorporates a series of step-down resistors which act as a voltage divider. The powertrain control module monitors this voltage which corresponds to the position of the gearshift selector lever (P, R, N, (D), 2 or 1). The powertrain control module uses this information to determine the desired gear and electronic pressure control pressure. The TR sensor is located on the outside of the transmission at the gearshift selector lever.
Symptoms: Harsh engagements, firm shift feel.
Diagnostic Trouble Codes: 634, 654, 667, 668, P0705, P0707, P0708, P1705.

Transmission Solenoid Body:
Description: The powertrain control module controls the E4OD transmission operation through four on/off solenoids and one Variable Force Solenoid. These solenoids and transmission fluid temperature sensor are housed in the transmission solenoid body assembly. All are part of the transmission solenoid body and are not serviced individually. Additionally, in 1995, the protection diodes that were on the solenoid body have been moved to the PCM. Refer to the following information for the functions of these solenoids.

The four on/off solenoids operate in the following manner:
When the solenoid is off, the fluid pressure feed is blocked by a check ball. The check ball is held in place by the solenoid piston.
When the solenoid is turned on by the PCM, the piston is pulled up, releasing the check ball and allowing fluid pressure to be applied to the check valves and/or other components controlled by the solenoid.

Electronic Pressure Control (EPC) Solenoid:
Description: The Electronic Pressure Control solenoid is a variable force solenoid. The variable-force type solenoid is an electro-hydraulic actuator combining a solenoid and a regulating valve. It supplies electronic pressure control which regulates transmission line pressure and line modulator pressure. This is done by producing resisting forces to the main regulator and the line modulator circuits. These two pressures control clutch application pressures.
Symptoms: Failed on — minimum electronic pressure control pressure (minimum transmission torque capacity). Limit engine torque (partial fuel shut-off, heavy misfire). Flashing transmission control indicator lamp.
Failed off — maximum electronic pressure control pressure, harsh engagements and shifts. May flash transmission control indicator lamp.
Diagnostic Trouble Codes: 624,* 625,* P1746,* P1747.*
CAUTION: The electronic pressure control pressure output from the variable force solenoid is NOT adjustable. Any modification to the electronic pressure control solenoid will affect the transmission warranty. (*Output circuit check, generated only by electrical condition.)

Torque Converter Clutch (TCC) Solenoid:
Torque converter clutch solenoid provides torque converter clutch control by shifting the converter clutch control valve to apply or release the torque converter clutch.
Symptoms: Failed on — engine stalls in drive at idle low speeds with brake applied or manual 2. Failed off — converter clutch never engages. May flash transmission control indicator lamp.
Diagnostic Trouble Codes: 629,* P0741,** P0743,** P1743, P1742, P1744. (*Output circuit check, generated only by electrical condition. **May also be generated by other non-electronic related transmission hardware condition.)

Coast Clutch Solenoid (CCS) 7M107:
The Coast Clutch Solenoid provides coast clutch control by shifting the coast clutch shift valve. The solenoid is activated by pressing the transmission control switch or by selecting the 1 or 2 range with the transmission gearshift selector lever. In manual 1 and 2, the coast clutch is controlled by the solenoid and also hydraulically as a fail-safe to ensure engine braking. In reverse, the coast clutch is controlled hydraulically and the solenoid is not on. NOTE: On certain applications, the coast clutch is controlled by the PCM in the overdrive position (TCS OFF) in gears 1, 2, and 3.
Symptoms: Failed on — Third gear engine braking with (D) range selected. Failed off — No third gear engine braking in overdrive cancel.
Diagnostic Trouble Codes: 626,* 628,** 643,* 652,* P0741,** P0743,* P1754.*
(*Output circuit check, generated only by electrical conditions. **May also be generated by other non-electronic related transmission hardware condition.)

Shift Solenoids 1 and 2:
Shift solenoids 1 and 2 provide gear selection of first through fourth gears by controlling the pressure to the three shift valves.

Shift Solenoid 1:
Symptoms: Improper gear selection depending on failure mode and manual lever position; refer to the Shift Solenoid Operation Chart. May flash transmission control indicator lamp.
Diagnostic Trouble Codes: 617,** 618,** 619,** 621,* P0750,* P0751, P0781,** P0782,** P0783.** (*Output circuit check, generated only by electrical conditions. **May also be generated by other non-electronic related transmission hardware condition.)

Shift Solenoid 2:
Symptoms: Improper gear selection depending on failure mode and manual lever position; refer to the Shift Solenoid Operation Chart. May flash transmission control indicator lamp.
Diagnostic Trouble Codes: 617,** 618,** 619,** 622,* P0755,* P0781,** P0782,** P0783,** P0756. (*Output circuit check, generated only by electrical conditions. **May also be generated by other non-electronic related transmission hardware condition.)


See this diagram for a 96; sim to your year. by Ford via Steve83


click to enlarge

Thanks Miesk,
So to my untrained eye, after reading all that, it appears it could be a few things...

1. The brake switch intermittently acting up resulting in all the symptoms, and no codes - seems pretty likely. Any way to test, or just replace?

2. TPS - I've checked this with the DVOM about 2 months ago, and it checked fine. Also if it is malfunctioning, codes usually result - Doubtful this is it. Is there another way to test?

3. VSS - speedo seems to be functioning fine. Maybe there is a minor issue. No codes though. Do you think this is a possibility? If so, how do I test?

4. Solenoids... specificaly the torque converter clutch solenoid. Seems like this would throw a code, but I guess it could fail intermittently. Seems unlikely.

The only thing I don't understand is the limp mode shifts. Tried to apply the brake and drive from a stop to get the hard shift(s). Was unable to replicate this failure, but I didn't try for long.

Am I on the right track gents? I'm in Portland Oregon this week, so I wont be able to tinker with it until the weekend.

78wookie said:

\\
yw

So to my untrained eye, after reading all that, it appears it could be a few things...

1. The brake switch intermittently acting up resulting in all the symptoms, and no codes - seems pretty likely. Any way to test, or just replace?
Yes, back-up to a wall, etc so you can see if brake lights come On when you hot brakes; look in rear view mirror; or pull sw and test it w/meter a few times
There is also the CC Recall and field service Update at large; has this been done yet?

2. TPS - I've checked this with the DVOM about 2 months ago, and it checked fine. Also if it is malfunctioning, codes usually result - Doubtful this is it. Is there another way to test? Not for now..later; since No codes but you can go thru this later if needed;
Throttle Position Sensor (TPS) Function & Diagnosis TSB 94-26-4 for 93-95; DTC 121,122,123, 124, 125, OBD II Code P0122 & P0123; "...The following is a list of vehicle symptoms which have been associated with the TPS, but can also be related to other vehicle components. Check engine light, Stalls, quits, hesitation/stumble, fast idle; To minimize the replacement of good components, be advised that the following non-EEC areas may be the issue: Excessive blow-by, PCV malfunction, Vacuum leaks, Fuel pressure, Throttle sticking or linkage binding. MANY VOLTMETERS WILL AUTOMATICALLY CHANGE RANGES WHEN MEASURING TPS OUTPUT FROM IDLE TO WOT. WHEN A VOLTMETER IS USED TO MEASURE TPS OUTPUT FROM IDLE TO WOT, THE METER SCALES OR CHANGES RANGES AUTOMATICALLY. THERE MAY BE AN ERRONEOUS METER DISPLAY UNTIL THE VOLTMETER HAS LOCKED TO THE APPROPRIATE VOLTAGE READING. THE ERRONEOUS METER DISPLAY DOES NOT REPRESENT A DEFECTIVE TPS. NOTE: IT IS RECOMMENDED THAT THE "RANGE LOCK" FEATURE ON MANY METERS BE SET FOR CHECKING TPS VOLTAGE..."
Source: by Ford via miesk5 at http://home.comcast.net/~miesk5/technical_service_bulletins.htm#technical_service_bulletins.htm

3. VSS - speedo seems to be functioning fine. Maybe there is a minor issue. No codes though. Do you think this is a possibility? If so, how do I test?
The VSS travels thru a fw connectors as well as the 4WABS Module (mine went bad and PSOM went screwy, tranny shifted hard, 4WABS Amber light and CEL lit, TCIL lit..) PSOM and then on to the PCM;
Speed Input Signal Test in 93-96 Bronco; "...NOTE: Only wiring harness end of connector is to be probed. * Connect Rotunda Digital Volt-Ohmmeter 014-00407 or equivalent to Pin 4 (speed in ) and Pin 5 (speed in -). * Does the voltage increase smoothly and continuously from 0 to approximately 3.5 volts as vehicle speed increases from 0 to 48 km/h (0 to 30 mph)? OR: If available, a frequency counter may be connected to Pin 4 (Speed in ) and Pin 5 (Speed in -). Does the displayed frequency of the signal increase smoothly and continuously from 0 to approximately 667 Hz at approximately 48 km/h (30 mph)? OR: * If neither a voltmeter nor frequency counter is available, vehicle speed control may be used as a good indicator. If it works normally, then the speedometer module is at least receiving a speed input signal and the wiring and sensor can be assumed to be good. Rear axle sensor should read 800-1400 Ohms across the pins, and more than 10 Ohms from the metal shell to either pin. To bypass the 4WABS module & feed the ABS signal directly to the PSOM, jumper 4WABS Control Module Bypass for PSOM Operation due to Bad 4WABS Control Module; "...To bypass the 4WABS module & feed the ABS signal directly to the PSOM, jumper 14 (CKT 530, LG/Y)to 21 (CKT 519 (LG/BK) & 39 (CKT 491 (O/LB)to 22 (CKT 523, R/PK)..." MIESK5 NOTE; see Steve's 4WABS Connectors Diagrams for 93-96 for the Module's Connector Pin-Outs..." http://www.supermotors.net/registry/media/170517_1
Source: by Steve83 (Steve, That dirty old truck) at SuperMotors.net
4. Solenoids... specificaly the torque converter clutch solenoid. Seems like this would throw a code, but I guess it could fail intermittently. Seems unlikely. Solenoid Resistance Tests (ohms); "...Shift Solenoid 1: 20-30 Shift Solenoid 2: 20-30 Torque Converter Solenoid: 20-30 Coast Clutch Solenoid: 20-30 Electronic Pressure Control: 4.0-6.5..." READ MORE
Source: by Steve83 (Steve, That dirty old truck) at http://www.fullsizebronco.com/forum/showthread.php?t=47918

CHECK CONNECTOR; hopefully the Heat Shield is still in-place to protect the conn, etc.
===
The only thing I don't understand is the limp mode shifts. Tried to apply the brake and drive from a stop to get the hard shift(s). Was unable to replicate this failure, but I didn't try for long. See Below

Am I on the right track gents? I'm in Portland Oregon this week, so I wont be able to tinker with it until the weekend.

Click to expand...

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Water Intrusion of Manual Lever Position/Transmission Range (MLP/TR) Sensor TSB 95-2-12 for 89-94
Source: by Ford via miesk5 at http://home.comcast.net/~miesk5/tec...f MLP/TR Sensor TSB 95-2-12 by Ford for 89-94

Adjustment Info; "...back-probe the MLP line with a volt meter while in Park, and set it to between 4.277 and 4.736 volts (ideally at 4.5065V, right in the middle of the two limits). As a "double-check" afterward, pull the lever down to 1st gear, and again test the MLP voltage; it should be between 0.293 and 1.167 volts, ideally in the middle at 0.73V..."
Source: by SigEpBlue (Steve) at http://fullsizebronco.com/forum/showthread.php?t=40055
Connector Pin-Out Diagrams
Source: by Ryan M (FireGuy50) at http://fordfuelinjection.com/files/Trans_harness.gif
Test, Pin-Point in 92-96; from Ford EVTM; "...The negative lead of the multimeter should be placed at the MLPS signal-return ground terminal at the MLPS. Check the resistance of the MLPS: The resistance of the MLPS (pins 30 and 46).." read more
Source: by Ford via alldata & justanswer @ http://ww2.justanswer.com/uploads/paynlessauto/2009-08-28_021637_222222.pdf

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DTC 67 & DTC 634; "E4OD Nagging Neutral Nonsense & Pinpoint Test, Manual Manual Lever Position (MLPS) also called Transmission Range (TR) Sensor. Some of the problems the MLPS can cause are wrong gear starts, TCC hunting, no 4th gear, engine stalling, high or erratic line pressure & a sudden neutral condition; The negative lead of the multimeter should be placed at the MLPS signal-return ground terminal at the MLPS...This sensor is responsible for more malfunctions than any other sensor in the sys- tem, and the kicker is that it seldom stores a code 67 or 634..."
Source: by Pete L at http://www.transonline.com/transdigest/magazines/1998-10/Shift Pointers/index.html

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Limp Mode; "...happens when the vehicle computer recognizes a problem in it's logic. When an expected signal value from a sensor is sent to the computer and is not within the computer's programmed specifications, "secondary" programs are activated by the computer to strive to protect the transmission from damage the improper sensor signal might cause to occur. In other words, the computer is always expecting certain signal values from certain sensors i.e. the temperature sensor, the speed sensor, the throttle position sensor, etc. As long as these signals are what it would normally expect for the conditions and is normal based on all the other signals it is receiving from other sensors, it acts normally and accordingly..." read more
Source: by autotransinc.com - site is gone - via webarchive.org
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bbl

dabranco said:

What I meant to say is that his PSOM could be in the early stages of failing, thats why I asked if he had any issues with his speedo and odometer reading correctly.

Click to expand...

NP pal, I messed-up my reply format; I have 1/2 of my reply in the shaded quote area and the rest below it.


The VSS travels thru a fw connectors as well as the 4WABS Module (mine went bad and PSOM went screwy, tranny shifted hard, 4WABS Amber light and CEL lit, TCIL lit..) PSOM and then on to the PCM;

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78W
re: " have the funny pig tailed wire harness with the stickers on it at the master cylinder. Could too much brake fluid cause the system to send a signal to the trans?"
Prob not, but why not inpsect that harness for fluid?
It is in the electr path, right? I forget, think it's shown in one of the diagrams I posted above.

Does the VSS itsef wear out? no, but it will fail completely or debris in rear diff could bugger the signal as described in ;
PSOM Pointer Waiver TSB 96-21-11 for 92-96; "..The speedometer needle may waver and or a light surge may occur on some vehicles...This may be due to slight dents/chips in either the exciter ring or the Vehicle Speed Sensor (VSS) and air gaps between the VSS and the exciter ring. Any slight dents, chips, etc., in either the exciter ring or VSS will create needle waver. Measure air gap between the VSS and exciter ring. It should be 0.38-0.51mm (0.015-0.020"). Check exciter ring runout per the same ring gear backface runout procedure of the appropriate model 1996 Powertrain/Drivetrain Service Manual, Section 05-00. Make sure the exciter ring is mounted correctly to the ring gear. If runout is more than 0.1mm (0.004"), perform the differential runout check per the procedure in the appropriate model 1996 Powertrain/Drivetrain Service Manual, Section 05-02A or 05-02D, to find cause and repair as needed. If all items listed above check good, replace the Instrument Cluster Assembly. Obtain the correct service part number from the Parts Catalogue and then contact the Electronic Odometer Exchange Center at (800) 259-9700 for U.S. Dealers and (800) 663-9974 for Canadian Dealers..." read more
Source: by Ford via miesk5 at http://home.comcast.net/~miesk5/tec...tm#PSOM Pointer Waiver TSB 96-21-11 for 92-96

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CHECK Tranny CONNECTOR for Solenoid Pack, and for the MLPS; hopefully the Heat Shield is still in-place to protect the Solenoid Pack connector, etc.
I know this is a lot to go thru, but the FORD EVTM will go even further.