Diagnostic Trouble Code (DTC) Information TCM-0A30

Condition 

Fig 1: Identifying Engine Control Module (ECM)

Courtesy of VOLVO CARS OF NORTH AMERICA.

The engine control module (ECM) transmits a signal on engine speed on the CAN network. The transmission control module (TCM) uses the signal to check the lock-up function.

The diagnostic trouble code (DTC) is stored if the control module detects that:

• There is no speed (rpm) signal from the engine control module (ECM) or the signal is faulty.

The control module's test for the diagnostic trouble code (DTC) starts in the event of:

• Ignition on and CAN network OK.

Substitute Value 

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

  HINT:  EMERGENCY MODE IN THE EVENT OF A FAULT 

• Neutral control function is blocked.
• Lock-up function is blocked.

Possible Source 

• Fault-trace the central electronic module (CEM).
• Locate the cause of the fault in the engine control module (ECM).
• Intermittent open circuit or short-circuit on the CAN lead between the engine control module (ECM) and the transmission control module (TCM).

Fault symptom[s] 

• General warning lamp lit
• Rough gear shift
• No gear shift
• No lock-up