Thread: Suspension Mystery Reoccurrence

Two days sequentially the "Suspension Fault" has appeared on initial start up with the vehicle parked in the garage.

First Occurrence

Over night temperatures were as low as 4 degrees.

In conjunction with the error message there was no ability to alter the suspension height up or down. The vehicle was driveable and the suspension remained at its initial height with all corners the same.

After driving 20 kms and parking the vehicle for 20 minutes where the ambient temperature increased to 16 degrees the vehicle started and displayed no "Suspension Fault" and the ability to adjust the height was fully functional.

Second Occurrence

Over night temperatures were as low as 7 degrees.

In conjunction with the error message there was no ability to alter the suspension height up or down. The vehicle was driveable and the suspension remained at its initial height with all corners the same.

After exiting the garage I connected my 0B2 reader, no DTCs were displayed and the suspension remained at its initial height.

After driving 15 kms and parking the vehicle for 4 hours where the ambient temperature increased to 18 degrees the vehicle started and displayed no "Suspension Fault" and the ability to adjust the height was fully functional.

I cannot identify any logical cause for this fault, extremely frustrating.

Appreciate a method to diagnose.

I researched that the suspension is controlled by the "Ride Level Module".

I scanned this module whilst there was no ability to select altering the vehicle height. Fault reported as "C1A13 Pressure does not decrease when venting gallery".

I had previously removed the compressor, checked the condition of the dryer desiccant, oven dried it and reassembled.

Removed the compressor, for the second time, tested there was no restriction to air passing through the dryer and the silica gel had not deteriorated.

Measured the coil resistance of the exhaust valve solenoid at 16 ohms and the continuity of conductors attached.

I dismantled the valve and found the solenoid slug very tight in the coil housing and a small foreign body in the passage connecting the valve to the compressor chamber.

I burnished the surfaces of the slug and ensured it was an unrestricted sliding fit in the coil housing. Cleaned the valve chambers and passage ways, confirmed O rings were not damaged and reassembled.

Compressor refitted, all connections leak tested, DTCs cleared in Ride level Module.

Ran the vehicle and found I could alter the suspension height multiple times without error or faults reported.

Early days, optimistic problem is resolved.