Engine Malfunction Test Procedure

During any diagnostic procedure, "hard failure" codes MUST be distinguished from "intermittent failure" codes. Diagnostic charts CANNOT be used to analyze "intermittent failure" codes, except as noted under Diagnostic Procedure. To determine "hard failure" codes and "intermittent failure" codes, proceed as follows:

1) Enter diagnostics. ECC will display trouble codes beginning with lowest numbered code. Each code will be displayed for 2 seconds until the highest code present has been displayed. Record all codes. Then, "-1.8.8" will appear.

2) Display procedure will repeat twice. On the third pass through the display, "hard failure" codes ONLY, will be displayed. Record all codes again. Any codes which appeared during the 1st and 2nd passes but not during the 3rd, are "intermittent failures". If no codes are displayed during the 3rd pass, there are no "hard failures", and the "CHECK ENGINE" light should have been out before entering diagnostics.

3) The 3rd pass ends with "-1.8.8" display. When trouble code sequence is completed, ".7.0" will display. If a code "51" is present, it must be diagnosed before further testing can begin. As long as "51" is displayed, no other diagnostic features are possible.

4) Begin diagnosis with the lowest numbered code, unless codes "51" and/or "16" are present. If codes "51" or "16" are shown, begin diagnosis with code "51", then proceed to code "16" since these codes may have an effect on setting of other codes. If no trouble codes are present, ECC will display "-1.8.8" for 2 seconds and then ".7.0".

NOTE: If vehicle exhibits performance problems and no codes are set, refer to the performance charts. Components recorded by trouble codes generally do not cause performance problems when no codes are stored.

If "intermittent failures" "13", "20", "33", "39", "44" or "45" appear, use diagnostic chart for corresponding "hard failure" code.