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Ignition Relay Circuit Diagnosis

NOTE: Ignition relay is also referred to as EFI relay.
  1. Perform diagnostic system check. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS in SELF-DIAGNOSTICS - PRIZM article. Repair any faults identified and go to next step.
  2. Check for an open IGN fuse (7.5-amp) and/or EFI fuse (15-amp). IGN fuse (7.5-amp) is located in junction block No. 2 behind storage box access cover on left side of instrument panel. EFI fuse (15-amp) is located in fuse/relay block No. 1 mounted on left front side of engine compartment to left of air cleaner. If both fuses are okay, go to next step. If either fuse is open, go to step  10 .
  3. Turn ignition on (engine off). Remove and reinstall EFI relay several times and listen for clicking sound from relay. EFI relay is located in fuse/relay block No. 1 mounted on left front side of engine compartment to left of air cleaner. If EFI relay does not click when removed and reinstalled, go to next step. If EFI relay clicks when removed and reinstalled, problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES - CARS article. Also check resistance of EFI relay. Because temperature may affect EFI relay performance, allow vehicle to sit outside overnight and after running engine for 30 minutes.
  4. Turn ignition off. Remove EFI relay. Turn ignition on (engine off). Using a test light connected to ground, probe cavity No. 9 of EFI relay socket. See WIRING DIAGRAMS article. If test light illuminates, go to next step. If test light does not illuminate, go to step  7 .
  5. Using a test light connected to ground, probe cavity No. 11 (Black/Orange wire) of EFI relay socket. See WIRING DIAGRAMS article. If test light illuminates, go to next step. If test light does not illuminate, go to step  9 .
  6. Turn ignition off. Using a test light connected to battery voltage, probe cavity No. 12 (White/Black wire) of EFI relay socket. If test light does not illuminate, go to step  8 . If test light illuminates, go to step  11 .
  7. Locate and repair open in ignition positive voltage circuit between EFI fuse (15-amp) and EFI relay cavities in fuse/relay block No. 1. See WIRING DIAGRAMS article. After repair, go to step  13 .
  8. Check for an open or poor connection in ground circuit (White/Black wire). Ground point is located behind battery at left front side of engine compartment. After repair, go to step  13 .
  9. Repair open in ignition positive voltage circuit (Black/Orange wire) between IGN fuse and EFI relay. See WIRING DIAGRAMS article. After repair, go to step  13 .
  10. Repair short to ground in IGN fuse and/or EFI fuse circuit. See WIRING DIAGRAMS article. After repair, go to step  13 .
  11. Locate and repair open or poor connection in EFI relay circuit (Black wire) from cavity No. 10 of EFI relay to component or system not receiving voltage. If fault is not located and repaired, go to next step. If fault is located and repaired, go to step  13 .
  12. Replace EFI relay. After repair, go to next step.
  13. Operate vehicle under same conditions as recorded for original symptom. If system operates properly, with no Diagnostic Trouble Codes (DTC) present, system is okay. If system does not operate properly and/or DTCs are present, go to DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - PRIZM article.
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