Fault code 0778: Diagnosis/troubleshooting: Initializing

The steering-angle sensor in Cayenne must be initialized after the following work is carried out:

Whenever the power supply is interrupted (NRA control lamp on).
The steering-angle sensor must be calibrated after all work on the running gear.

NOTE: Calibration of the steering-angle sensor must be performed on a measuring platform. First, the level control module must be coded successfully and the steering-angle sensor must be initialized. The steering-angle sensor must be calibrated after work has been carried out on the running gear in the area of the front axle.

DIAGNOSIS/TROUBLESHOOTING PROCEDURE

Work instruction			Display OK	If not OK
1	Initialize steering-angle sensor	Switch on ignition. Position wheels straight ahead. From the straight-ahead position, turn the steering wheel approx. '15°' to the left and '15°' to the right (past the straight-ahead position). Drive the vehicle straight ahead at a speed of '> 4 km/h for at least 1 second'.	After successful initialization, the stored fault code is erased from the fault memory and the NRA control lamp goes out. → End	Go to Step 2
2	Check steering-angle sensor calibration using 9588 Porsche System Tester II	Running gear set according to Porsche specifications. Wheels in straight-ahead position and steering wheel horizontal. Steering wheel may be turned by max. '± 2.0°' from the horizontal position for driving straight ahead.	After successful calibration, the stored fault code is erased from the fault memory. → End	Go to Step 3
3	Mechanical fault	Examine moving parts for damage and check mobility.	Go to Step 4	The steering-angle sensor is integrated into the steering column switch and must be replaced along with this if its functionality is mechanically impaired. → End
4	Read out steering column switch control module, fault memory and check circuit for short or open circuit	Eliminate faults in accordance with 'Diagnosis/troubleshooting' for steering column switch control module.	If electric circuit is OK: Go to Step 5	Repair wiring harness circuit. → End
5	Check CAN drive	Localize faults in accordance with CHECKING INSTRUCTIONS/CAN DATA BUS .	If CAN drive is OK: Go to Step 6	Repair wiring harness. → End
6	Replace steering-angle sensor		The steering-angle sensor can only be replaced together with the steering column switch. → End	Go to Step 7
7	Replace level control module		→ End