Diagnostic trouble code (DTC) information

Condition 

Fig 1: Identifying Lock-Up Pressure Switch

Courtesy of VOLVO CARS OF NORTH AMERICA.

The automatic transmission control module (TCM) receives a signal from the pressure switch for lock up PS4 to control the lock-up valve position. Diagnostic trouble code (DTC) TCM-008D is stored if the lock-up solenoid has stuck in the open or closed position, transmitting a faulty signal to the control module.

Substitute Value 

• TBD

Possible Source 

• The pressure switch for lock-up is jammed.
• Contact resistance in the terminals.

Fault symptom[s] 

• The automatic transmission warning lamp flashes.
• No lock-up function.
• Harsh gear shifting.

HINT: Harsh gear shifting can be caused by: 

• 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.