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i have a 94 Bronco Eddie Bauer 5.0. I pulled the codes and came up with a 121,626,629,637,and 654. I have searched everywhere trying to find solutions to rectify these problems. Does anyone out there know where I can find these answers? The reason I pulled codes is because at times my Bronco wont shift out of 2nd.
 

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yo James,
DTC 121, 122, 123, 124, 125 & DTC P0122, P0123 & P1121 in TSB 94-26-4 "...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 tccoa.com (http://www.tccoa.com/articles/mn12-techinfo/tsb/tsb-94-26-4.pdf)
READ MORE

Throttle Position Sensor Testing, Replacement and Adjustment by Seattle FSB
http://fullsizebronco.com/forum/showthread.php?t=203080

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.)

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.)

DTC 637 - TOT sensor circuit above maximum voltage possible causes: Damaged TOT sensor. Open harness circuit(s). Damaged processor. or the transmission was overheated. 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.
Source: by Ford via miesk5 at FSB

DTC 522 & 654 indicate the gear selector was not in Park during Self-Test; "...Possible causes: Misadjusted linkage. Open or short in harness circuits. Damaged TR sensor. Damaged Powertrain Control Module (PCM). OR CHECK THIS OUT, TECHNICAL BULLETIN # 230A, TRANSMISSION: E4OD SUBJECT: No upshift, 4th gear starts, harsh upshifts, neutrals out after shifts APPLICATION: Ford-E/F Series, Bronco DATE: Jan 1995 NOTE: Click on image to make it larger. All of these concerns can be the result of an inappropriate Manual Lever Position (MLP) sensor signal. The MLP sensor consists of six resistors connected in series (ganged). The resistance of the MLP sensor will vary based on which range the transmission is in. The MLP circuit can be checked using the following steps. (Step 1) Check the MLPS ground: Turn the ignition on. The voltage on pin 46 (sensor ground ) should not exceed .1v. If the voltage is excessive, add an additional ground to the existing ground wire (figure 2). NOTE: Click on image to make it larger. Figure 2 Splice an additional ground from the existing ground wire to a known good ground. The negative post of the battery is the best. This view is of the pins of the MLP connector pins. NOTE: Click on image to make it larger. (Step 2) Check the MLPS voltage: The voltage at pin 30 should vary-in increments- according to the position of the manual lever (figure 3). MLP voltage (ignition on) should be within 20% of these specifications. Note It is recommended that you use a break-out box. If a break-out box is not available, you will need to pierce the wires to pins 30 and 46 for these tests. NOTE: Click on image to make it larger. (Step 3) Check the resistance of the MLPS: The resistance of the MLPS (pins 30 and 46) should change-in increments-with the position of the manual lever (figure 4). Note If this test is being done with a break-out box, disconnect the computer first (make sure the ignition is off). If this test is being done without a break-out box, disconnect the MLPS from the vehicle harness. Note Testing beyond this point will include tests of the harness. Consult the appropriate repair manual for this..."
Source: by fordbronco1995 ("JUICE") at FSB DTC 522 & 654 indicate the gear selector was not in Park during Self-Test; "...Possible causes: Misadjusted linkage. Open or short in harness circuits. Damaged TR sensor. Damaged Powertrain Control Module (PCM). OR CHECK THIS OUT, TECHNICAL BULLETIN # 230A, TRANSMISSION: E4OD SUBJECT: No upshift 4th gear starts, harsh upshifts, neutrals out after shifts APPLICATION: Ford-E/F Series, Bronco DATE: Jan 1995 NOTE: Click on image to make it larger. All of these concerns can be the result of an inappropriate Manual Lever Position (MLP) sensor signal. The MLP sensor consists of six resistors connected in series (ganged). The resistance of the MLP sensor will vary based on which range the transmission is in. The MLP circuit can be checked using the following steps. (Step 1) Check the MLPS ground: Turn the ignition on. The voltage on pin 46 (sensor ground ) should not exceed .1v. If the voltage is excessive, add an additional ground to the existing ground wire (figure 2). NOTE: Click on image to make it larger. Figure 2 Splice an additional ground from the existing ground wire to a known good ground. The negative post of the battery is the best. This view is of the pins of the MLP connector pins. NOTE: Click on image to make it larger. (Step 2) Check the MLPS voltage: The voltage at pin 30 should vary-in increments- according to the position of the manual lever (figure 3). MLP voltage (ignition on) should be within 20% of these specifications. Note It is recommended that you use a break-out box. If a break-out box is not available, you will need to pierce the wires to pins 30 and 46 for these tests. NOTE: Click on image to make it larger. (Step 3) Check the resistance of the MLPS: The resistance of the MLPS (pins 30 and 46) should change-in increments-with the position of the manual lever (figure 4). Note If this test is being done with a break-out box, disconnect the computer first (make sure the ignition is off). If this test is being done without a break-out box, disconnect the MLPS from the vehicle harness. Note Testing beyond this point will include tests of the harness. Consult the appropriate repair manual for this..."
Source: by fordbronco1995 ("JUICE") at FSB

Manual Lever Position/Transmission Range (MLP/TR) Sensor - E4OD Controls Overview, Sensors, DTC (s) & Diagram; "... 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. Harsh engagements, firm shift feel. DTC 634, 654, 667, 668, P0705, P0707, P0708, P1705..." READ MUCH MORE
Source: by Ford via Steve83
http://www.supermotors.net/registry/media/704885

Manual Lever Position Sensor (MLPS) 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 FSB http://fullsizebronco.com/forum/showthread.php?t=40055
 
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