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IV. DTC Display Method
V. HCU Diagnosis
Use the scan meter to diagnose the Hydraulic Control Unit (HCU), select the "3 HCU diagnosis" in the
options and perform the following procedures.
* Perform the above step 2 - 8 test for each wheel in the following order LF RF LR RR.
* If the result of some one of the above steps is different from the normal result, it indicates that the
corresponding element fails the normal operation, please check the corresponding element.
* You can use “ESC” button to end the test to return the function menu in any place in the screen where
there is “return” displayed to return to the function menu.
Code Displayed
Never happened before No DTC
Happened before Occasional DTC
Never happened before Non-occasional DTC
Happened before
Occasional DTC and Non-
occasional DTC
System Problem
There is no problem current ABS
Warning Light does not light up
)
The problem still exists
(
ABS
Warning Light goes on
)
Step Action Screen Display Normal Result
1 HCU diagnosis – hydraulic pump test Pump motor operates
2 LF Wheel——Depress the brake pedal
3
LF Wheel—— normally open valve
open, normally closed valve closed,
wheel locked
?
Wheel locked
4
LF Wheel—— normally open valve
closed, normally closed valve closed,
wheel locked
?
Wheel locked
5
LF Wheel — — normally open valve
closed, normally closed valve open,
wheel can rotate freely
Wheel can rotate freely, the
pedal rebound, the cylinder
motor operating noise is audible
6
LF Wheel—— normally open valve
closed, normally closed valve closed,
wheel can rotate freely
Wheel can rotate freely
7
LF Wheel — — normally open valve
open, normally closed valve closed,
wheel locked
?
Wheel locked, the pedal sag
slightly
8
Release the brake
pedal
Depress and hold
the brake pedal
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