LEMON Manuals: Even more car manuals for everyone
Home >> Oldsmobile >> 1998 >> Regency >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control Systems Tests W/Codes >> Diagnostic Trouble Codes >> DTC P0336 - 18X Reference Signal Circuit >> Diagnostic Procedures

Diagnostic Procedures

  1. Perform POWERTRAIN ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK . Read and record FREEZE FRAME and/or FAIL RECORDS data for each DTC set. After performing OBD system check, go to next step.
  2. Attempt to start engine. If engine starts and runs, go to next step. If engine does not start and run, see NO START DIAGNOSIS in BASIC TESTING article.
  3. Using scan tool, clear DTC P0336. Start and allow engine to idle for one minute. Read DTCs. If DTC P0336 resets, go to next step. If DTC does not reset, go to DIAGNOSTIC AIDS.
  4. Disconnect ICM and PCM harness connectors. Check for open or short to ground in 18X reference circuit between ICM and PCM harness connectors. Repair as necessary. After repairs, go to step 11). If no problem is found, go to next step.
  5. Reconnect ICM connector. Using DVOM, check voltage on 18X reference circuit at PCM harness connector while cranking engine. If voltage is about 3 volts, go to step 8). If voltage is not as specified, go to next step.
  6. Check for faulty connections at ICM. Repair as necessary. After repairs, go to step 11). If connections are okay, go to next step.
  7. Replace ICM. After replacing module, go to step 11).
  8. Check for incorrect harness routing near secondary ignition components, ignition coil arcing to wiring harness or ICM. Check ignition coils for cracks, carbon tracking or other signs of damage. Check for secondary ignition wire(s) arcing to wiring harness. Repair as necessary. After repairs, go to step 11). If no problem is found, go to next step.
  9. Check for faulty connections at PCM. Repair as necessary. After repairs, go to step 11). If connections are okay, go to next step.
  10. Replace PCM. Program replacement PCM using required equipment. After replacing PCM, go to next step.
  11. Read and record FAIL RECORDS data for DTC P0336. Operate vehicle within conditions noted in FAIL RECORDS data. Using scan tool, read SPECIFIC DTC. If scan tool displays DTC P0336 FAILED THIS IGN, return to step 2). If scan tool does not display DTC P0336 FAILED THIS IGN, repair is complete.
scientia non olet · About LEMON Manuals