Diagnostic Aids

Normal Scan voltage varies between .1-1.0 volt, while in closed loop. Code 13 sets in one minute, if voltage remains between .35-.55 volt. The system will go into open loop after about 15 seconds.

Verify a clean, tight ground connection for circuit No. 413. Open in circuits No. 412 or 413 will result in a Code 13.

If Code 13 is intermittent, see INTERMITTENTS in TESTS W/O CODES article.

Fig 1: Circuit Diagram Code 13 (1 of 2)

Courtesy of GENERAL MOTORS CORP.

Fig 2: Flow Chart Code 13 (2 of 2)

Courtesy of GENERAL MOTORS CORP.