Powertrain Control Module (PCM) - 545RFE
P0755-2C SOLENOID CIRCUIT
Special Tools:
Theory of Operation
The Transmission Control System uses five electronically controlled solenoids that allow hydraulic fluid to be applied to various friction elements (clutches), which enables the gear requested. The continuity of each solenoid circuit is periodically tested. Each inactive solenoid is turned on for a few milliseconds, then off. Each active solenoid is turned off for a few milliseconds, then on. This pulsing of voltage to the solenoid causes an inductive spike which can be sensed by the Transmission Control System. If an inductive spike is not sensed by the Transmission Control System during the continuity check, it is tested again. If the test fails three consecutive times, the appropriate Diagnostic Trouble Code (DTC) is set. If the solenoid test is run in response to a gear ratio or pressure switch error, one failure will result in setting the appropriate DTC.
- When Monitored:
Initially at power-up, then every 10 seconds thereafter. The solenoid circuits will also be tested immediately after a gear ratio or pressure switch error is detected.
- Set Condition:
After three consecutive solenoid continuity test failures, or one failure if test is run in response to a gear ratio or pressure switch error.
NOTE: This DTC is strictly an electrical fault and cannot be caused by any internal transmission failure other than an open in the Transmission Solenoid/TRS Assembly. If the Transmission Solenoid/TRS Assembly is in need of replacement - do not replace the Valve Body.
Always perform the Pre-Diagnostic Troubleshooting Procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
1. CHECK DTCs
1. With the scan tool, check DTCs.
Are there any TIPM TCM Power Control Circuit or TCM Power Input DTCs present?
Yes
- Testing and Inspection Perform the appropriate diagnostic procedure.
No
- Go To 2
2. CHECK TO SEE IF P0755 IS PRESENT
1. Turn the ignition off to the lock position.
2. Remove the Ignition Switch Feed fuse from the TIPM.
CAUTION: Removal of the Ignition Switch Feed fuse from the TIPM will prevent the vehicle from being started in gear.
WARNING: The Ignition Switch Feed fuse must be removed from the TIPM. Failure to do so can result in possible serious or fatal injury.
3. Install the Transmission Simulator.
4. Ignition on, engine not running.
5. With the scan tool, actuate the 2C Solenoid.
Did the 2C Solenoid LED blink on and off on the Transmission Simulator?
Yes
- Go To 3
No
- Go To 5
3. CHECK THE TRANSMISSION SOLENOID/TRS ASSEMBLY
1. With the Transmission simulator still connected, continue to actuate the 2C solenoid for two minutes.
2. After two minutes of actuation, with the scan tool, stop the actuation and check for transmission DTCs.
Did the DTC P0755 reset during the actuation test?
Yes
- Go To 5
No
- Go To 4
4. WIGGLE TEST WITH TRANSMISSION SIMULATOR
1. With the Transmission simulator still connected, continue to actuate the 2C solenoid for another two minutes while wiggling the related wiring harness and connectors.
2. With the scan tool, stop the actuation and check for transmission DTCs.
Did the DTC P0755 reset during the actuation test?
Yes
- Repair wiring harness or connectors as necessary.
- Perform the 545RFE TRANSMISSION VERIFICATION TEST. 545RFE Transmission Verification Test
No
- Replace the Transmission Solenoid/TRS Assembly. Note: Do NOT replace the entire Valve Body. Transmission Solenoid And TRS Assembly - Removal
- Perform the 545RFE TRANSMISSION VERIFICATION TEST. 545RFE Transmission Verification Test
5. CHECK THE (T219) 2C SOLENOID CONTROL CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT
1. Turn the ignition off to the lock position.
2. Disconnect the Transmission Simulator.
3. Disconnect the PCM harness connectors.
4. Measure the resistance between the (T219) 2C Solenoid Control circuit and all other circuits in the Transmission Solenoid/TRS Assembly harness connector.
Is the resistance below 5.0 Ohms between the (T219) 2C Solenoid Control circuit and any other circuit(s) in the Transmission Solenoid/TRS Assembly harness connector?
Yes
- Repair the (T219) 2C Solenoid Control circuit for a short to another circuit(s).
- Perform the 545RFE TRANSMISSION VERIFICATION TEST. 545RFE Transmission Verification Test
No
- Go To 6
6. CHECK THE (T219) 2C SOLENOID CONTROL CIRCUIT FOR AN OPEN
1. Connect the PCM Pinout Box to the PCM C4 harness connector.
CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the (8815A) to perform diagnosis.
2. Measure the resistance of the (T219) 2C Solenoid Control circuit between the Transmission Solenoid/TRS Assembly harness connector and the appropriate terminal of the PCM Pinout Box.
Is the resistance above 5.0 Ohms?
Yes
- Repair the (T219) 2C Solenoid Control circuit for an open.
- Perform the 545RFE TRANSMISSION VERIFICATION TEST. 545RFE Transmission Verification Test
No
- Go To 7
7. CHECK THE (T219) 2C SOLENOID CONTROL CIRCUIT FOR A SHORT TO GROUND
1. Measure the resistance between ground and the (T219) 2C Solenoid Control circuit.
Is the resistance below 5.0 Ohms?
Yes
- Repair the (T219) 2C Solenoid Control circuit for a short to ground.
- Perform the 545RFE TRANSMISSION VERIFICATION TEST. 545RFE Transmission Verification Test
No
- Using the schematics as a guide, check the Powertrain Control Module (PCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace and program the PCM. With the scan tool, perform Quick Learn.
- Perform the 545RFE TRANSMISSION VERIFICATION TEST. 545RFE Transmission Verification Test