Transfer Case Control Module (TCCM): Diagnostics

WARNING: This page is about a different car, the 2017 Jaguar XJ, 2016 Jaguar XJ, 2015 Jaguar XJ, 2014 Jaguar XJ, and 2013 Jaguar XJ. However, it is still accessible from the selected car via links, so may be relevant.

If the TCCM is unable to operate the on demand multiplate clutch correctly, it issues a message on the HS CAN Powertrain bus which is displayed in the IC (Instrument Cluster) message center as '2 Wheel Drive Only. Traction Reduced' . The TCCM will disable the actuator and the transfer case will operate in RWD only.

If a DTC (Diagnostic Trouble Code) is stored relating to input voltage failure or HS CAN Powertrain bus failure, the vehicle harness, connectors and other system modules must be investigated before replacing the TCCM.

If the message '2 Wheel Drive Only. Traction Reduced' appears temporarily and a DTC is stored relating to over temperature, the failure is unlikely to be corrected by replacement of the TCCM. Cause of overheat must be investigated.

If the TCCM requires replacement, the procedure detailed in the applicable repair procedure must be followed. Adaptive parameters must be copied from old unit and transferred to the new unit.