With Scan Tool

When a fault occurs in the anti-lock brake system, the brake control module will activate the amber Anti-Lock Warning Lamp. Before performing diagnostic procedures upon the anti-lock brake system when the warning lamp comes on, ensure the EBCM connector and all other system electrical connectors are secure and fuses are satisfactory. Refer to ABS Functional Check(s). Sometimes, use of a compact spare will activate a wheel sensor diagnostic trouble code and deactivate the anti-lock system; if this occurs, cycle the ignition switch to reset the system. Functional Check

The EBCM performs an automatic (AUTO) test once each ignition cycle when vehicle reaches approximately 4 mph. The AUTO test cycles each solenoid valve and pump motor to check component operation. If any error is detected during this test, the EBCM will set a diagnostic trouble code. This test may be heard and felt while it is taking place and should be considered a normal mode of operation.

The EBCM can display diagnostic trouble codes only when the "Diagnostic Service Mode" has been entered. There are two ways to enter the diagnostic service mode: using a TECH 1 scan tool or observing Anti-Lock warning lamp flash codes. The use of a TECH 1 computer is recommended for diagnosing ABS faults.