Diagnostic Trouble Code (DTC) Information TCM-0071
Condition
To prevent the car engine from starting with a gear engaged, which results in the car lurching forwards when started, the car is equipped with an immobilizer function. Built into the transmission control module (TCM) are two hall sensors. Their task is to detect whether the gear selector is in position. Starting is permitted in P or N. The transmission control module (TCM) has a signal cable connected directly to the engine control module (ECM). The signal notifies the engine control module (ECM) whether it is possible to start the engine or not. When the voltage level on the signal cable is grounded it is permitted to start. The diagnostic trouble code (DTC) is stored if the transmission control module (TCM) discovers that the signal is always grounded.
Substitute Value
- None.
Possible Source
- Contact resistance in the terminals
- Short-circuit to ground in the signal cable
- Internal fault in the transmission control module (TCM).
Fault symptom[s]
- The engine fails to start
- The engine starts with the gear selector in positions R and D.