Test Procedure

Turn ignition off to reset PRC control module before each test. Verify vehicle has completed VISUAL INSPECTION. Ensure steering wheel is straight. Turn on analog VOM. Turn on ignition to activate KEY ON, ENGINE OFF TEST. See Fig 1 . Refer to TEST STEPS in left column for procedure to follow. Then count needle sweeps and record all service codes. The chart shows voltmeter needle sweeps and durations. Notice same code pattern can sometimes indicate different faults in different test steps.

Fig 1: Performing Key On Engine Off Test

Courtesy of FORD MOTOR CO.