Failure Code Determination

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. Then "- 1.8.8" will appear.
   PROGRAMMED ECM TROUBLE CODES
   
   

   Code	Circuit Affected
   12	No tach signal.
   13	Oxygen sensor not ready.
   14	Shorted coolant sensor circuit.
   15	Open coolant sensor circuit.
   16	Generator voltage out of range.
   18	Open crank signal circuit.
   19	Shorted fuel pump circuit.
   20	Open fuel pump circuit.
   21	Shorted TPS circuit.
   22	Open TPS circuit.
   23	EST circuit problem in run mode.
   24	Speed Sensor circuit.
   25	EST circuit problem in by-pass mode.
   26	Shorted throttle switch circuit.
   27	Open throttle switch circuit.
   28	Open 4th gear circuit.
   29	Shorted 4th gear circuit
   30	ISC circuit.
   31	Shorted MAP sensor circuit.
   32	Open MAP sensor circuit.
   33	MAP/BARO sensor correlation.
   34	MAP signal too high.
   35	Shorted BARO sensor circuit.
   36	Open BARO sensor circuit.
   37	Shorted MAT sensor circuit.
   38	Open MAT sensor circuit.
   39	TCC engagement.
   44	Lean exhaust signal.
   45	Rich exhaust signal.
   51	PROM error.
   52	ECM memory reset indicator.
   60	Transmission not in "DRIVE".
   63	Car speed exceeds maximum limit.
   64	Car exceeds maximum acceleration limit.
   65	Coolant temperature exceeds maximum limit.
   66	Engine RPM exceeds maximum limit.
   67	Shorted "SET" or "RESUME" circuit.
   .7.0	System ready for further tests.
   .7.1	Cruise control brake circuit test.
   .7.2	Throttle switch circuit test.
   .7.3	Drive (ADL) circuit test.
   .7.4	Reverse circuit test.
   .7.5	Cruise ON/OFF circuit test.
   .7.6	SET/COAST circuit test.
   .7.7	RESUME/ACCELERATION circuit test.
   .7.8	INSTANT/AVERAGE circuit test.
   .7.9	RESET circuit test.
   .8.0	A/C clutch circuit test.
   -1.8.8	Display check.
   .9.0	System ready to display engine data.
   .9.5	System ready for output cycling or in fixed spark mode.
   .9.6	Output cycling.
   .0.0	All diagnostics complete.

2. Display procedure will repeat twice. On the 3rd pass through the display, "hard" failure codes ONLY, will be displayed. 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 be begun. As long as "51" is displayed, no other diagnostic features are possible.
4. Begin code diagnosis with the lowest code number unless code "16" is present. Code "16" should always be diagnosed first (except Code "51") since it may have an affect on setting of other codes. If no trouble codes are present, ECC will display "-1.8.8" for 2 seconds and then ".7.0".