HAIMA 7 - Troubleshooting

Anti-lock brake system (ABS control unit)
P-38
S/N Symptom
1 Turn the ignition switch in the ON position, but the warning light of ABS control unit is not lit up
2
Turn the ignition switch in the ON position, the warning light of ABS control unit keeps lit for
more than 4s.
3
When parking or driving the vehicle, the warning light of ABS control unit is lit and won’t go off
until the ignition switch has been turned to the OFF position.
4 When parking or driving the vehicle, the warning light of ABS control unit flashes on
5
Although the warning light indication system of ABS control unit is normal, but faults really exist
in the system.
Diagnostic diagram
Possible causes
Fault diagnostic items
ABS
control unit CM
Instrument component Warning light circuit of ABS control unit Battery Charge system CM power supply of ABS control unit CM GND1 of ABS control unit Conventional brake HU brake lines and chosen itinerary Wheel speed sensor of ABS control unit Tire size and pressure
The ignition switch turned in the
ON position, but the warning light
of ABS control unit is not lit.
X X X
The ignition switch turned in the
ON position, but the warning light
of ABS control unit keeps lit
within 4s.
X X X X X
When parking or driving the
vehicle, the warning light of ABS
control unit is lit and won’t go off
until the ignition switch has been
turned in the OFF position.
X X X X
When parking or driving the
vehicle, the warning light of ABS
control unit flashes on
X X X X X X
Although the warning light
indication system of ABS control
unit is normal, but faults really
exist in the system.
X X X
Troubleshooting