E DTC C1140 Low Speed ABS Control Operation

NOTE: Refer to the PINPOINT TEST section of the Flow of Diagnosis before beginning this pinpoint test. Flow of Diagnosis

NORMAL OPERATION:
During a braking event in which any given wheel goes to lock, the anti-lock control system operates to prevent wheel lock-up.

FAULT DESCRIPTION:
A hydraulic problem that would cause a wheel to stay locked for a predetermined amount of time. The vehicle must be above 6.4 km/in (4 mph) and in anti-lock control mode. Diagnostic trouble code (DTC) C1140 will be set in response to a wheel that has gone to lock-up and is not recovering.

POSSIBLE CONTRIBUTING CONDITIONS:
- Internal hydraulic anti-lock actuator leak.
- Seized disc brake caliper.
- Brake anti-lock sensor dropout at speeds below erratic brake anti-lock sensor detection.
- Faulty pump.
- Pinched or crushed brake line.

E1- Check Fault Repeatability
- Turn ignition switch to "OFF".
- Connect scan tool to Data Link Connector (DLC).
- Turn ignition switch to "RUN".
- Clear all DTC's using the scan tool.
- Perform the Drive Cycle Test. Refer To Inspection and Verification.
- Retrieve DTC's from ABS memory using the scan tool.
- Is DTC C1140 retrieved?
YES - Go to E2.
NO - Repeat the System Pre-Check.

E2- Check Low Speed ABS Control Operation
NOTE: Wetting down the test area will aid in performing the test.

- Drive the vehicle at approximately 16 km/h (10 mph)

NOTE: A momentary lock-up is permissible. An assistant should be used to monitor the wheels during the stop.

- Apply the brakes hard enough to lock all four wheels.
- Does one wheel lock consistently?
YES - Go to Diagnosis by Symptom and Start with "ABS Misfire"
NO - Repeat the System Pre-Check.