After my 4ws has been disconnected the entire weekend, the car turns left after I connected it again, and I can hear a motor on the rear rack!
Does anybody know have to calibrate it, or is something broken?
Sorry for my bad English!
The rear rack has a centering spring (internally) and two solenoid dump valves (near the hydraulic lines) that relieve pressure when the system is shut off. The combination of these two devices return the rear wheels to straight ahead.
The rear rack (from below) has two inspection plugs: one opens a hole to the inside, the other is pointed in a blind hole.
The hole to the inside views the base of the syncronization shaft. When the rack is centered, a dimple is present. The other pointed plug is used to pin this shaft in place for repairs or alignments. The system must be off and the connection to the front rack removed or you will damaged this dimple if anything turns!
Disconnect the shaft running to the front rack. Center the dimple for the rear. Center the front steering in the straight ahead position, then reconnect the synchro shaft.
The front is now centered, and the rear is now centered mechanically. Inside the rear rack the hydraulic valve is now centered so there should be no "steering" when the engine is re-started.
REMOVE THE POINTED CENTERING PLUG FROM THE DIMPLE ON THE SHAFT BEFORE DRIVING THE CAR OR YOUR DIMPLE WILL BECOME A GROOVE IN SHORT ORDER. t Put the pointed plug back into the blank hole and the short flat-faced plug back into the other hole to seal up the rack.
If the car continues to turn left, there is something more with the rear rack either hydraulically (the valve) or electrically (the stepper motor).
If all of the above checks good, there is a steering sensor problem or a brain-fart in the ECU. Those inupts/commands tell the stepper motor what to do.
The first link in my signature will take you to my Cardomain account. Page 5 starts the scan of the 4WS training manual section.