1. Connect HHT to data link connector (X11/4) as shown in connection diagram (see section 0). 2. Ignition: ON 3. Perform Quick Test with HHT and readout DTC'S. Note: The HHT, via its display indicates only the defective electrical components or refers to the corresponding Test step. 4. If no DTCs are stored in memory, then proceed with 13

DTC	Note	Possible cause	Test step/Remedy
	Valid for diagnostic version 1	Internal fault within transfer case control module (N78).	Replace N78
	Valid for diagnostic version 1	Fault with voltage supply to transfer case range selection motor (A55) or position signal sensor at transfer case range selection motor is unplausible.	Wiring, Plug connectors, A55