Symptom Chart

Because the overall function of the system is dependent on sub-systems, it is possible to misinterpret displays in the message center as being terrain response faults when they are actually a result of a fault in one of the sub-systems.

Refer to the table below for help in deciding when to investigate terrain response faults and when the fault is likely to be in a sub-system.

Symptom	Description	Possible Causes	Action
Message center display indicating a sub-system fault	The message center indicates to the driver that a fault has occurred and in which sub-system	Any sub-system fault supported by the message center	For details of the available messages, refer to the relevant section of the workshop manual. Carry out a complete vehicle DTC read and follow the diagnostic routine(s) indicated.
Message center display: System fault special programs not available , terrain response switch operation normal	This message will display when a sub-system fault has occurred if the driver attempts to change the special program, and at each ignition on cycle for 5 seconds until the fault is rectified	Any sub-system fault supported by the message center	For details of the available messages, refer to the relevant section of the workshop manual. Carry out a complete vehicle DTC read and follow the diagnostic routine(s) indicated.
Message center display: System fault special programs not available , ALL terrain response switch LEDs illuminated	CAN circuit errors	CAN circuit: short circuit to ground CAN circuit: short circuit to power CAN circuit: high resistance	Carry out a complete vehicle DTC read and follow the diagnostic routine(s) indicated.
Special program changes not available	User error	Engine not running Rock crawl selected with transfer box in high range Special program change attempted with ABS or DSC active This includes ABS cycling as part of HDC Special program change attempted with an overheat condition present in the center or rear differential	Refer to the relevant section of the workshop manual. Make sure that the driver is familiar with the correct operation of the system.