Diagnostic trouble code (DTC) information

Condition 

Fig 1: Identifying Transmission Control Module (TCM)

Courtesy of VOLVO CARS OF NORTH AMERICA.

Each time the ignition is switched on, the control module checks the ROM memory circuit in the control module. Diagnostic trouble code (DTC) AT-412 is stored the second time the ignition is switched on if the control module registers a fault in the memory circuit.

Substitute Value 

• None.

Possible Source 

• Defective control module.

Fault symptom[s] 

• The warning lamp in the combined instrument panel flashes.