4T65EV Transmission

Diagnostic trouble code (DTC) information

Condition




The automatic transmission control module (TCM) receives speed signals from the ABS control module and from the transmission speed sensor on the transmission. The transmission control module (TCM) uses the signals to select the correct gear. The control module derives and compares the speed signal from the ABS system with the transmission speed and the engine speed (RPM) at the transmission. Diagnostic trouble code (DTC) TCM-001F is stored if the control module registers that the signal from the speed sensor is missing.

Substitute value
- None.

Possible source
- Contact resistance in the terminals.
- Open-circuit on power supply.
- Open-circuit in the signal cable.
- Defective transmission speed sensor.

Fault symptom[s]
- General orange warning lamp lit.
- Malfunction indicator lamp (MIL) lit.
- No lock-up function.
- Harsh gear shifting.

Hint: Harsh gear shifting can be caused by:
- No reduction of line pressure when shifting.
- No reduction of line pressure when moving the gear selector between positions P-R, N-R and N-D.
- No torque limiting request to engine control module (ECM) when shifting.