Code Format

Service codes are 2-digit numbers representing the results of the SELF-TEST. These numbers are read on the STAR tester or as timed pulses (needle sweeps) on the analog ohmmeter. The pulse format is as follows:

• 1/2 sec. "ON" time, for each digit.
• 2 sec. "OFF" time, between each digit.
• 4 sec. "OFF" time, between codes.
• 8-12 sec. between "FAST" (System Test) and "SERVICE" codes.

Fig 1: Meter Hook-Up for Reading Codes

Courtesy of FORD MOTOR CO.