Diagnostic Procedure

Refer to ENTERING ON-BOARD DIAGNOSTICS to retrieve fault codes. If fault codes are NOT present and/or DRB-II (Diagnostic Readout Box-II) is used, proceed to TEST CH-1, BATTERY TEST.

NOTE: When using trouble shooting charts for diagnosis, DO NOT skip any steps in chart or incorrect diagnosis may result.

Before proceeding with diagnosis, the following precautions must be followed:

Vehicle must have a fully charged battery and functional charging system. Refer to both TROUBLE SHOOTING and TESTING (ON-VEHICLE) .
Probe SBEC connector from pin side. DO NOT backprobe SBEC connector.
DO NOT cause short circuits when performing electrical tests. This will set additional fault codes, making diagnosis of original problem more difficult.
DO NOT use a test light in place of a voltmeter.
Always repair lowest fault code number (CHECK ENGINE light) or first fault displayed (DRB-II) first.
Always perform verification procedure test after repairs are made.
Always disconnect DRB-II after use.
Always disconnect DRB-II before charging battery.