Guided Fault Finding

WARNING: This page is about a different variant/trim than selected.

Information

Always read the fault memory out first. Any fault codes must be corrected using Guided Fault Finding in PIWIS Tester .

Symptom	Fault detection	Possible causes	Solution
Gradual loss of pressure Vehicle lying to one side after a long time Longer than average regulating times No reaction to driver's request Fault memory entries: Lift time exceeded Leak in pressure accumulator	Observe vehicle height over a long period of time and try to find the leak using commercially available leak detection spray	Leak in air-spring strut/air spring	Replace air-spring strut/air spring > 433019 REMOVING AND INSTALLING FRONT AIR-SPRING STRUT or carry out repairs > 433037 DISASSEMBLING AND ASSEMBLING FRONT AIR-SPRING STRUT , replace rear air spring > WM, 434319 REMOVING AND INSTALLING AIR BELLOWS > WM, 430117 BLEEDING AND FILLING THE LEVELLING SYSTEM
		Leak in air lines or valve unit	Check tightening torques for air line connections, check insertion depth of air lines (color marking), replace air line
Vehicle lying to one side No leaks in the system	Carry out Guided Fault Finding using the Porsche System Tester	Vehicle level sensor faulty	Replace vehicle level sensor > WM, 431819 REMOVING AND INSTALLING FRONT LEVEL SENSOR
		Linkage or holder for vehicle level sensor is bent	> WM, 431919 REMOVING AND INSTALLING REAR LEVEL SENSOR
		Sensor for body not installed/screwed correctly	Visual inspection of sensors for body. > 433419 REMOVING AND INSTALLING SENSOR FOR BODY

Symptom	Fault detection	Possible causes	Solution
Vehicle is too high Vehicle cannot be lowered	1.) Check that the vehicle has sufficient ground clearance	Vehicle position is raised	Look for signs of damage and check clearance around the air-spring struts/air springs and anti-roll bars
	2.) Check air line and line routing	Air line blocked, kinked or frozen	Replace kinked air lines; carefully clean frozen and blocked air lines using compressed air
	3.) Valve unit blocked	Dirt in valve unit	Replace valve unit > WM, 432355 REPLACING VALVE UNIT
	4.) Compressor/valve block blocked	Dirt in compressor/valve block	Replace compressor > WM, 431519 REMOVING AND INSTALLING COMPRESSOR
	5.) Carry out Guided Fault Finding using the Porsche System Tester	Check relays, plug contacts, wire harness and fuses in the vehicle electrical system Drain valve in the compressor faulty/leaking/open	Replace compressor > WM, 431519 REMOVING AND INSTALLING COMPRESSOR
		Drain valve in compressor or control valves in valve block do not work Valve unit does not work	Replace compressor > WM, 431519 REMOVING AND INSTALLING COMPRESSOR
6.) If no faults were found after carrying out Step 7.), the compressor is faulty		Compressor faulty	Replace compressor > WM, 431519 REMOVING AND INSTALLING COMPRESSOR
Vehicle is too low Vehicle cannot be raised or can only be raised very slowly	1.) Check that the vehicle has sufficient ground clearance	Vehicle position is raised	Look for signs of damage and check clearance around the air-spring dampers and anti-roll bars
	2.) Check air line and line routing	Air line blocked, kinked or frozen	Replace kinked air lines; carefully blow out frozen and blocked air lines using compressed air
	3.) Valve unit blocked	Dirt in valve unit	Replace valve unit > WM, 432355 REPLACING VALVE UNIT
	4.) Compressor/valve block blocked	Dirt in compressor/valve block	Replace compressor > WM, 431519 REMOVING AND INSTALLING COMPRESSOR
	5.) Carry out Guided Fault Finding using the Porsche System Tester	Check relays, plug contacts, wire harness and fuses in the vehicle electrical system Drain valve in the compressor faulty/leaking/open	Replace compressor > WM, 431519 REMOVING AND INSTALLING COMPRESSOR
		Drain valve in compressor or control valves in valve block do not work	Replace compressor > WM, 431519 REMOVING AND INSTALLING COMPRESSOR
	6.) If no faults were found after carrying out Step 7.), the compressor is faulty	Compressor faulty	Replace compressor > WM, 431519 REMOVING AND INSTALLING COMPRESSOR
Rapid loss of pressure	Vehicle lying to the left or right; when you try to switch to a different level, you can hear air coming from the faulty air spring	Air-spring strut/air spring is faulty	Replace air-spring strut/air spring > 433019 REMOVING AND INSTALLING FRONT AIR-SPRING STRUT or carry out repairs > 433037 DISASSEMBLING AND ASSEMBLING FRONT AIR-SPRING STRUT , replace rear air spring > WM, 436619 REMOVING AND INSTALLING REAR SPRING DAMPER > WM, 430117 BLEEDING AND FILLING THE LEVELLING SYSTEM
		Air line torn off	Repair air line > WM, 430117 BLEEDING AND FILLING THE LEVELLING SYSTEM
Insufficient damping	Test drive: Adjust the damping level while the vehicle is in motion. You should feel a significant change in the damping effect when driving on uneven road surfaces. Also check for hard "knocks" (rumbling noises).	Electric connector for PASM faulty	Check electric connector for PASM and replace if necessary.
		Damping adjustment valve faulty	Replace shock absorber > WM, 433037 DISASSEMBLING AND ASSEMBLING FRONT AIR-SPRING STRUT , > WM, 429319 REMOVING AND INSTALLING REAR SHOCK ABSORBER
		Vibration damper worn	Replace shock absorber > WM, 433037 DISASSEMBLING AND ASSEMBLING FRONT AIR-SPRING STRUT , > WM, 429319 REMOVING AND INSTALLING REAR SHOCK ABSORBER If shock absorbers are worn, clean air line system