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Diagnostic Trouble Code (DTC) Information



Condition







The transmission speed signal is transmitted by a sensor on the transmission. The transmission control module (TCM) uses the signal to determine the input shaft speed after the torque converter. This signal is used to compare the transmission speed and vehicle speed. The transmission control module (TCM) uses this comparison to calculate gear-shift timing. RPM and vehicle speed data affects the adjustment of system pressure, lock-up function control and engine torque- reduction. The result is smooth gear-shifting. The control module derives and compares the transmission speed, engine speed (RPM) and speed (RPM) at the transmission. Diagnostic trouble code (DTC) TCM-0023 is stored if the control module registers that the speed (RPM) signal is missing.

Substitute Value
- No torque reduction
- No lock-up

Possible Source
- Contact resistance in terminals.
- Open-circuit on power supply.
- Open-circuit in the signal cable.
- Defective input 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 adaptation of the gear slippage times at high altitude (High Altitude Compensation).
- 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.