Diagnostic trouble code (DTC) information
Condition
The signal for the input speed comes from a sensor inside the transmission control system. The transmission control module (TCM) bases its calculation of the speed of the input shaft after the torque converter on this signal. The signal is used to compare the speed of the gearbox with the vehicle speed. Using this comparison, the control module can calculate the gear shifting points. The information on RPM and speed affects the adjustment of the system pressure and the reduction of the engine torque when changing gear. This results in smoother gear changes. The information is also used to control the lock-up function.
If the transmission control module (TCM) registers that the circuit to the gearbox input speed sensor is missing, the diagnostic trouble code (DTC) is generated.
The diagnostic trouble code (DTC) can be diagnosed when driving normally.
Substitute Value
- Auxiliary program Emergency mode 1 in the transmission control module (TCM) has started.
Possible Source
- Open circuit in power supply or signal lead.
- The signal cable is short-circuited to ground.
- Gearbox input speed sensor not working.
- Internal fault in transmission control module (TCM).
Fault symptom[s]
- Malfunction indicator lamp (MIL) lit.
- General warning lamp lit
- No lock-up function.
- Harsh gear changing
- No gear changing.