HAIMA 7 - Page 370

Anti-lock brake system (ABS control unit)
P-40
6
Disconnect the control modular joint of ABS
control unit, connect the SST only at the harness
side of vehicle. Use the SST joint and connect
the lead of alarm light to the bodywork
grounding.
Whether the alarm light of ABS control unit
goes off when the ignition switch in the ON
position turned.
Yes
Check and maintain the harnesses
between the modular PS and
grounding of ABS control unit
No
Check and repair the harness
break-circuit and the alarm light
circuit in the instrument between the
modular and alarm light of ABS
control unit
3
When parking or driving in the vehicle, the alarm light of ABS control unit is lightened
up and goes off until the ignition switch is turned in the OFF position.
Tips of
troubleshooting
The control modular of ABS control unit detected the faults, but the normal operation of
control modular of ABS control unit will be detected when the ignition switch is turned
on again;
The ABS control unit detected the low battery voltage, but it will detest that the control
modular of ABS control unit is in normal operation when the ignition switch is turned
on again,
Steps Test items Operation
1
Carry out the DTC test. See—— OBD
function, Check of ABS control unit/TCS,
Whether the DTC has been saved in the
memory？
Yes
Carry out the inspection as per the
corresponding DTC.
No Go to the next step
2 Whether the battery voltage is normal？
Yes Go to the next step
No Check the battery and charge system.
3
Whether the battery voltage is normal when
the engine runs idle and has electric load？
Yes
Check and repair the harnesses
between the power lead of control
modular of ABS control unit and
grounding 1
No Check charge system
4
When parking or driving in the vehicle, the alarm light of ABS control unit alarm light
flashes
Tips of
troubleshooting
There are intermittent break-circuit in the alarm light circuit of ABS control unit;
The control modular of ABS control unit is repeatedly On and Off(power supply and
grounding wire etc are intermittently break-circuited);
Steps Test items Operation
1
Whether the control modular joint of ABS
control unit is in good connection？
Yes Go to the step 3
No
Connect properly the joint and go to
the next step
2
Whether the alarm light of ABS control unit is
relit when starting the engine and driving the
vehicle with the alarm light On？
Yes
Intermittently poor contact,
Check the joint box leadoff control
modular in the ABS control unit.
No Go to the next step
Steps Test items Operation