Page 148 - Workshop Manual - Aumark (BJ1051)

04-4
Diagnose- ABS system

ABS Diagnosis Descriptions

The ABS control unit has a fault self-diagnosis feature. Once the unit detects a brake system

malfunction, it will light up malfunction light and, at the same time, generate a corresponding DTC
and store it in memory, and then the system will enter different fail-safe procedures automatically
according to severity level of the malfunction.
1. Two ways available to read DTC after an ABS system malfunction occurs
• Read through BC on ASR (ABS) blink code light.
• Read using a special tester.
(a) Blink code
• DTC obtained by means of flicker frequency of ASR (ABS) blink code light on the
meter.
• After a malfunction blink code appears, you can perform troubleshooting according to
the code and its corresponding trouble description.
• Blink codes sometimes appear and are read inaccurately in real processes and
deviations will occur to bring untruth to your trouble diagnosis. Therefore, you had

04 better use a trouble diagnosis tester to perform diagnosis.
• You should delete corresponding malfunction blink code as quickly as possible after a
trouble is cleared.
(b) SAE code
• Such a code can only be read using a dedicated trouble detector.
• When troubleshooting a vehicle equipped with on-board diagnostics (OBD), you must
connect the vehicle to special diagnostic equipment with OBD function and then read
out various data output from the ABS control unit on your vehicle. When the ABS
control unit detects a malfunction, OBD rules require the on-board computer to light
up the malfunction indicator light on the instrument panel.
• If a malfunction represented by a DTC recorded in the ABS control unit does not
reappear in 3 successive stroke tests, the ABS malfunction indicator light will go out
automatically, but the DTC will still be recorded in memory of the unit.

2. Checking battery voltage
(a) Battery voltage: 18-30V.
(b) If the voltage is below 18V, be sure to replace battery before entering the next step.
3. Checking ABS malfunction indicator light

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