Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information

Condition




The transmission control module (TCM) receives a signal about input and output speed from the transmission's two speed sensors. There is a determined ratio for each gear and the signals help calculate the transmission control module (TCM) gear ratio. Diagnostic trouble code (DTC) TCM-012D or TCM-012E is stored depending on the cause of the fault if the transmission control module (TCM) registers that the transmission is mechanically in neutral position although the gear selector has been moved to D or R.

TCM-012D
The diagnostic trouble code can be diagnosed when driving forward (gear position "D"), engine rpm above 600 rpm, throttle damper angle open more than 10%, transmission's oil temperature above +0 °C and brake pedal unaffected.

TCM-012E
The diagnostic trouble code can be diagnosed when reversing (gear position "R"), engine rpm above 600 rpm, throttle damper angle open more than 10%, transmission's oil temperature above +0 °C and brake pedal unaffected.

Substitute value
- Auxiliary program Emergency mode 1 in the transmission control module (TCM) has started.

Hint: Emergency mode in case of malfunction Emergency Mode In Case of Malfunction

Possible source
- Internal malfunction in the transmission's control system.
- Mechanical fault in gearbox. Gearbox components worn and causing slip or system pressure too low.

Fault symptom[s]
- General warning lamp lit
- Malfunction indicator lamp (MIL) lit.
- Abnormally slipping gears.
- Harsh gear changing
- No gear changing.