JAC HFC4DA1-2C, Maintenance Manual

Page: 573 / 801

ABS
ABS
ABS ABS Anti-lock
Anti-lock
Anti-lock Anti-lock Brake
Brake
Brake Brake System
System
System System
96
S/N Operating Step Operation Detection
Result Next Step
2 Using diagnostic
instrument to perform
component testing for
solenoid valve of ABS
hydraulic
governor
with ECU
Remarks:
①
Before testing solenoid valve, please test he reflux pump
to see if it operates normally.
②
Two repair men are required to finish this test.
(a) Turn off the ignition switch;
(b) Connect the diagnostic instrument to DLC.
(c) One repair man should sit in the vehicle and the vehicle
should be lifted by lifter with wheels suspended.
(d) Turn on the ignition switch with engine off.
(e) Apply the “Component Test” function of diagnostic
instrument to activate the solenoid valve as per prompt of
diagnostic instrument.
(f) Firstly, test the oil inlet valve and oil outlet valve of left
front wheel, during which, the repair man in the vehicle
should depress the brake pedal with force and hold it.
①
Conventional braking phase:
Normal state: The repair man outside cannot rotate the
left front wheel by hand.
②
Boosting phase: Use diagnostic instrument to access the
“boosting phase”.
Normal state: The repair man outside cannot rotate the
left front wheel by hand.
③
Pressure maintenance phase: Use diagnostic instrument to
access the “pressure maintenance phase”.
Normal state: The repair man outside cannot rotate the
left front wheel by hand.
④
Pressure reducing phase: Use diagnostic instrument to
access the “pressure reducing phase”.
Normal state: The repair man outside can rotate the left
front wheel by hand.
(g) Perform testing for right front, left rear and right rear
wheels in sequence.
The test results should be the same as those of left front
wheel.
Normal Go to the next step.
Abnormal Replace ABS control
unit assembly.
3 Checking pin voltage
of
ABS hydraulic
governor with ECU
When using multimeter:
(a) Turn off the ignition switch
(b) Remove connectors from ABS hydraulic governor with
ECU.
(c) Use multimeter to measure the voltage at the power
terminal and grounding terminal of solenoid valve.
Remarks:
If no jumper box is applied, the normal detection cannot
be ensured.
Normal value: U=9.3
～
16.9V
Normal Replace ABS hydraulic
governor with ECU.
Abnormal Go to the next step.
4 Checking connecting
wires, connectors and
40A fuse
(a) Check if 25A fuse is normal.
(b) Check the charging system, such as generator/battery and
its connecting wire.
(c) Ensure the grounding terminal is well grounded.
Normal Go to the next step.
Abnormal Replace or repair
connecting
wire/connector or fuse.
5 Final inspection. (a) Clear DTC.
(b) ABS and EBD warning lamps shall go out shortly after the ignition switch is turned on
(c) With the ignition switch turned on, C0121 DTC shall no longer appear after self-checking is
finished by system.
(d) Perform Step 2 in this procedure and the testing result is normal.