Diagnostic trouble code (DTC) information

Condition

Fig 1: Identifying Control Module

Courtesy of VOLVO CARS OF NORTH AMERICA.

The transmission control module (TCM) and engine control module (ECM) communicate via a standardized serial interface - CAN (Controller Area Network) -to exchange information. Both control modules send and receive information via two signal cables - CAN H and CAN L. Diagnostic trouble code (DTC) TCM-DF13, TCM-DF14, TCM-DF15, TCM-DF16 or TCM-DF18 is stored (depending on the fault and cable) if the transmission control module registers an open-circuit in the CAN wiring or a short-circuit to supply voltage or ground.

Possible Source

The cable between (TCM) terminal #27 and (ECM) terminal #27 (CAN H):

TCM-DF13: short-circuit to supply voltage
TCM-DF15: short-circuit to ground
TCM-DF18: open-circuit.

The cable between (TCM) terminal #26 and (ECM) terminal #57 (CAN L):

TCM-DF14: short-circuit to ground
TCM-DF16: short-circuit to supply voltage
TCM-DF18: open-circuit.

Fault symptom[s]

Fault symptoms for DF13 - DF16

The warning lamp for the automatic transmission flashes.

Fault symptom for DF18

The warning lamp for the automatic transmission flashes.