WABCO iABS 2S/1M Standard, Maintenance Manual

Page: 154 / 188

154
Troubleshooting
Condition
Experienced
Action to Take Troubleshooting Detail
s
Verify the operation of the 3/2
solenoid valve 472 170 997 0.
Apply 12v DC power and ground to pins 1 and 2 in the
3/2 valve's bayonet connector. The solenoid should
energize and dump the air on the tag axle. Removing
the power and ground will cause the tag axle air bags
to re-in
fl ate.
Tag Axle
Comes to
Rest on Axle
Bump Stops
Using TOOLBOX PLUS™
Software, ensure there are no
active faults. Repair and clear all active faults. Cycle the ECU power.
Ensure the tag axle system is
plumbed correctly.
Refer to Figure 9.15.
Verify the 3/2 solenoid valve
has optional components
installed. Refer to Figure 9.19.
Check for air leaks.
Ensure no air leaks at the 1/4" to 3/8" adapter, the
residual pressure valve and the check valve. Refer to
Figure 9.19.
Tag Axle is
Intermittent
Using TOOLBOX PLUS™
Software, ensure there are no
active faults. Repair and clear all active faults. Cycle the ECU power.
Verify tag axle system is
plumbed correctly and check for
air leaks. Refer to Figure 9.15.
Ensure that the air volume
capacity of the trailer meets
trailer OEM standards for
operating a tag axle. Verify the output of the towing vehicle's air compressor
to the trailer.
Optional
Tag Axle
Indicator
Light Does
Not Function
Using TOOLBOX PLUS™
Software, ensure there are no
active faults. Repair and clear all active faults. Cycle the ECU power.
Verify the type of tag axle 12
volt DC indicator lamp.
The lamp must be an incandescent lamp or a load-
resistor LED lamp.
Verify the lamp is correctly
wired to the switch and
indication lamp cable 449 827
XXX 0. The red wire is hooked to power and the brown wire is
hooked to ground.
Ensure that the correct
indication lamp type is
activated.
While entering the parameters to program the iABS
with Tag Axle function, ensure that Tag Axle Status
Lamp is either LED or Incandescent Lamp.
Verify the switch and indication
lamp cable 449 827 XXX 0
integrity.
Using a volt/ohm meter, check for shorted or open
circuits on the switch and indication lamp cable. Refer
to Figure 9.16.
Optional Tag
Axle LED
Indicator
Lamp Stays
on Faintly
Inspect the type of indicator
lamp.
Replace generic LED lamp with a load-resistor LED or
incandescent lamp. The red wire is hooked to power
and the brown wire is hooked to ground.