15
XL-AS20015BM-en-US Rev E · 2022-10-05 · Amendments and Errors Reserved · © SAF-HOLLAND, Inc., SAF-HOLLAND, HOLLAND, SAF,
and logos are trademarks of SAF-HOLLAND S.A., SAF-HOLLAND GmbH, and SAF-HOLLAND, Inc.
Troubleshooting
PROBLEM
POSSIBLE CAUSE
POSSIBLE REMEDY
Tire Pressure HIGH
and Warning Light
is OFF
Tire over-inflation
Let system function with power and air, the system will relieve the tire pressure to the
current setpoint.
Tire Pressure in-spec
and Warning Light
is ON
Inadequate supply pressure
Supply pressure must be a minimum of 10psi greater than the desired tire pressure.
Correct as necessary.
Inadequate supply voltage
Supply voltage must be a minimum of 12V DC. Correct as necessary
Defective Pressure Protection Valve
Replace pressure protection valve
Note: System cannot use the same PPV as the air suspension. A dedicated port on the
air tank is required with a dedicated pressure protection valve.
Defective electronic regulator
assembly
Replace electronic regulator assembly
Loose/leaking air lines or fittings
Spray all air lines and fittings with soapy water and repair leaks as needed
Leaking rotary union
Replace rotary union
Tire Pressure in-spec
and Warning Light
is OFF
System is working as designed, no issue
Air Leak from axle
vent
Damaged/loose airlines or
connections inside the axle
Remove spindle plug assemblies, inspect air line connections and repair as necessary
Leaking rotary union
Replace rotary union
Loose and/or leaking air lines
and/or fittings
Spray all air lines and fittings with soapy water and repair leaks as needed
Air Leak from Tire
Hose
Overtightened connections
Tire hose fittings should be hand tightened. Over-tightened fittings can damage the
o-rings inside the fitting. Inspect o-rings for damage and replace as necessary.
Brake air tank
de-pressurized or low
pressure
Defective pressure protection valve
Replace pressure protection valve
Note: System cannot use the same PPV as the air suspension. A dedicated port on the
air tank is required with a dedicated pressure protection valve.
Air leak between air tank and
pressure protection valve
Spray all air lines and fittings with soapy water and repair leaks as needed
LED warning light
flashing SOS
Electronic regulator assembly error
Reset the module by cycling the power off then back on or clear the faults within
the mobile app. If this doesn't eliminate the light flashing, replace the module.
