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So, new here to FSB. Would like some opinions on how to go about diagnosing and repairing a trouble code, code 98 (Electronic pressure control driver open in EEC (E4OD) or Hard fault present). Not really sure where to even begin tracking and hunting this problem down. I understand that this code causes the engine to go into limp mode, and wont allow my O/D to engage in the c6, thus killing and I mean Killing me in gas, and a big lack of engine power it seems also.

I have had this truck for a few months, and havent really started driving it much untill it started getting cold and I couldn't ride the motorcycle. The truck has driven this way since I bought it. Any help on where to start figuring out whats causing this is much appreciated.:beer
 

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yo,
WELCOME!

DTC 98 Hard fault present; Failure Mode Effects Management (FMEM) FMEM is an alternate system strategy in the PCM designed to maintain vehicle operation should one or more sensor inputs fail. When a sensor input is perceived to be out-of-limits by the PCM, an alternative strategy will be initiated. The PCM will substitute a fixed in-limit sensor value and will continue to monitor the faulty sensor input. If the faulty sensor operates within limits, the PCM will return to the normal engine running strategy. Engine Running DTC 98 or 998 will be displayed when FMEM is in effect. The Malfunction Indicator Lamp (MIL)/Message will remain on when FMEM is in effect. The MIL will come on while the engine is operating in Failure Mode Effects Management (FMEM) or Hardware Limited Operation Strategy (HLOS) modes. The light will stay on for at least 10 seconds, then stay on as long as the fault causing it is present. If the MIL flashes quickly (less than 10 seconds), the MIL circuit should be checked for concerns. In FMEM mode, the PCM is receiving a sensor signal that is outside the limits set by the calibration strategy. In this mode, the PCM uses an alternate engine control strategy to maintain reasonable vehicle operation in spite of the fault. The DTC associated with this fault is stored in Keep Alive Memory (KAM). If the fault is no longer present, the light will turn off and the vehicle will return to the normal vehicle strategy. The DTC stored when the light was on is kept in Continuous Memory for the next 80 warm-up cycles (40 cycles on some applications) and then erased.
This Continuous Memory DTC can be accessed by running the Key On Engine Off Self-Test.
It should have some code(s) come up that will help narrow this down

The engine temperature must be greater than 50° F for the Key On Engine Off (KOEO) Self-Test and greater than 180° F for the Key On Engine Running (KOER) Self-Test.
Run it around to heat the engine up and shift thru all gears incl Reverse. Then turn off all accessories/lights, etc.

Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch.

Do Key On Engine Off (KOEO) portion first.

Look Codes up in my broncolinks.com site using the new Search function.

And Post em here according to:
KOEO
&
KOER

Also,
The Keep Alive Memory (KAM) within the processor must always have voltage supplied to it. This voltage is supplied by the Keep Alive Power (KAPWR) circuit (Pin 1) that connects directly to the battery. KAM contains adaptive parameter tables that allow the processor to adapt to different operating requirements. It also contains the Continuous Memory codes. Continuous Memory codes will be erased any time KAPWR is disconnected (i.e. battery disconnected, processor disconnected, breakout box installed, open in the wire, etc.). If KAM fails within the processor, all Continuous codes will also be erased.
&
Powertrain Control Module KAM Test Error Indicates the PCM has experienced an internal memory fault. However there are external items that can cause this DTC. Reprogramming
Battery terminal corrosion
KAPWR to PCM interrupt/open
Loose battery connection
Damaged PCM (less likely)


EDIT; forgot a major thAng, sorry, got caught up in multi tasking;
Clearing Keep Alive Memory:
To clear the KAM, disconnect the battery negative terminal for five minutes or more (preferably 15 minutes).

Adaptive Strategy Relearn Procedure:
After repairs have been made and the KAM cleared drive the vehicle for at least ten miles to allow the PCM to relearn the values for optimum performance.

Note: During the ten mile relearn drive, the vehicle may exhibit some driveability symptoms. These should be eliminated when the KAM has relearned the operating values.
 

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I will try to rerun the test later tonight. When I ran it yesterday, on the KOEO, i originally recieved a 32 o code during the test, cleaned the egr valve and sensor, and it fixed the issue. during the contiuous memory portion of the KOEO test, code 51 c came up, have not addressed that yet.

When I ran the KOER test, code 51 c still came up, and this time code 98 r came up. also after a few moments with the tester running, for some reason the engine began idling at around 2k?
 

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yo,
DTC 51 - ECT sensor signal is greater than the Self-Test maximum of 4.6 volts;
was engine temp still greater than 180° F for the Key On Engine Running (KOER) Self-Test? If not, then the 51 will show;

If temp was over 180:
Open circuit in harness
Sensor signal short to power
Damaged PCM - no way!...lol..let's not get into this!
Improper harness connection
Damaged sensor

Remove the ECT sensor, If you see some rust in it clean it by sanding the surface using a fine grit sandpaper, Also check the connector and wiring. Reinstall and check for codes, if some are present change the unit.

DTC 21, 51, 61 or 116, 117, 118 "...Failure in either the circuit or temperature sensor will show code 21, 51, 61 or 116, 117, 118.Unplug the harness connector. First, check the signal voltage at the connector with the key on, engine off. Should be approximately 5.0v. Then, check the resistance of the sensor cold. Should be between 58,750 to 40,500 ohms. Plug in the harness connector and warm up the engine to normal operating temperature. Then, unplug and check the resistance of the sensor hot. Should be 3,600 to 1,840 ohms...'
Source: by Seattle FSB (SeattleFSB) at FSB http://fullsizebronco.com/forum/showthread.php?t=184491

btw, See my site for testing [email protected] http://www.broncolinks.com/index.php?index=540

& In testing;
Voltage Reference (VREF) is a conditioned regulated constant 5v DC power source supplied by the PCM.

Have a Great Thanksgiving Friend!
 

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So, new here to FSB. Would like some opinions on how to go about diagnosing and repairing a trouble code, code 98 (Electronic pressure control driver open in EEC (E4OD) or Hard fault present). Not really sure where to even begin tracking and hunting this problem down. I understand that this code causes the engine to go into limp mode, and wont allow my O/D to engage in the c6, thus killing and I mean Killing me in gas, and a big lack of engine power it seems also.

I have had this truck for a few months, and havent really started driving it much untill it started getting cold and I couldn't ride the motorcycle. The truck has driven this way since I bought it. Any help on where to start figuring out whats causing this is much appreciated.:beer
I am confused too. An all stock 88 will not have an E4OD and a C6 doesn't have overdrive. Is this on a different vehicle? Am I missing something else?

tim
 

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I am confused too. An all stock 88 will not have an E4OD and a C6 doesn't have overdrive. Is this on a different vehicle? Am I missing something else?

tim
Yo TIM,
I was too, but I see that he prob looked the Code up and saw that def as applicable to E4OD somewhere; so I decided to go SOP and yak about Self Testing:thumbup
 

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I am confused too. An all stock 88 will not have an E4OD and a C6 doesn't have overdrive. Is this on a different vehicle? Am I missing something else?

tim
:stupid

Bronco Engine, Transmission, Drivetrain History! For your reference…


The Ford C6 transmission was essentially an upgraded version of the C4, Ford's base three-speed auto. It features three forward speeds and reverse. The C6 uses heavier-duty components to handle the additional torque of larger engines and the additional loads of heavier vehicles, such as F-Series trucks.

The only transmission option in a 1988 5.8L Bronco was the C6.
 
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