LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Pontiac >> 2001 >> Aztek Base, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System & Component Testing >> Ignition System >> Ignition Relay (CNG)
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Ignition Relay (CNG)

  1. Perform OBD system check. See ON BOARD DIAGNOSTIC (OBD) SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article. Go to next step.
  2. Check CNG and IGN E fuses, located in underhood fuse block. If fuses are okay, go to next step. If one or both fuses are faulty, go to step  14.
  3. Turn ignition on. Using test light connected to ground, probe both sides of each fuse. If test light does not illuminate at all terminals, go to next step. If test light illuminates at all terminals, go to step  5.
  4. Check fuse contacts and power source. See WIRING DIAGRAMS article. Repair as necessary. After repairs, go to step  23.
  5. Using scan tool, attempt to communicate with AF ECU. If AF ECU does not communicate, go to next step. If scan tool communicates, go to step  8.
  6. Turn ignition off. Disconnect AF ECU connectors. Turn ignition on. Using test light connected to ground, probe AF ECU connector C002 terminals No. 15 (Pink wire) and No. 16 (Orange wire). If test light illuminates at both terminals, go to next step. If test light does not illuminate at both terminals, go to step  15.
  7. Using test light connected to battery voltage, probe AF ECU connector C002 terminals No. 21, 22, 23 and 24 (Black wire). If test light does not illuminate at all terminals, go to step  15. If test light illuminates at all terminals, go to step  21.
  8. Turn ignition off for 30 seconds. Monitor Fuel Indicator Light (FIL), located on fuel gauge select switch. Turn ignition on. If FIL does not illuminate, go to next step. If FIL illuminates, go to step  10.
  9. Turn ignition on. Using test light connected to ground, backprobe ignition relay terminal No. 87 (Red wire). If test light does not illuminate, go to step  11. If test light illuminates, diagnose fuel gauge select switch light. See FUEL GAUGE SELECTOR SWITCH/FUEL INDICATOR LIGHT .
  10. Using test light connected to ground, backprobe ignition relay terminal No. 87 (Red wire). Turn ignition off. If test light stays on, go to step  16. If test light does not stay on, recheck system. See ON BOARD DIAGNOSTIC (OBD) SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article.
  11. Backprobe ignition relay terminal No. 30 (Orange wire). If test light illuminates, go to next step. If test light does not illuminate, go to step  17.
  12. Ensure ignition is on. Backprobe ignition relay terminal No. 85 (Pink wire). If test light illuminates, go to next step. If test light does not illuminate, go to step  18.
  13. Remove ignition relay. Connect test light between relay connector terminal No. 85 (Pink wire) and No. 86 (Black wire). If test light illuminates, go to step  20. If test light does not illuminate, go to step  19.
  14. Diagnose and repair short causing fuse to blow. See WIRING DIAGRAMS article. After repairs, go to step  23.
  15. Repair open circuit. After repairs, go to step  23.
  16. Replace ignition relay or repair short to power on Pink wire. After repairs, go to step  23.
  17. Repair open circuit on Orange wire. After repairs, go to step  23.
  18. Repair open circuit on Pink wire. After repairs, go to step  23.
  19. Repair open on Black wire. After repairs, go to step  23.
  20. Replace ignition relay. After repairs, go to step  23.
  21. Check AF ECU terminal contact. If no problem is found, go to next step. If any problem is found, repair as necessary. After repairs, go to step  23.
  22. Replace AF ECU. Program AF ECU. Go to next step.
  23. Reconnect all components and connectors. Using scan tool, clear all DTCs. Turn ignition off for 30 seconds. Start engine. Test drive vehicle. If no problems are found, MIL operates properly and no DTCs are set, test is complete. If any problems are found, MIL does not operate properly or DTCs are set, perform OBD system check. See ON BOARD DIAGNOSTIC (OBD) SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article.
scientia non olet · About LEMON Manuals