Fuel Injector Circuits (Frontier & Xterra)
- Start engine. Listen to each fuel injector. If every injector clicks, system is okay. If any injector does not click, go to next step.
- Turn ignition off. Disconnect inoperative injector harness connector. Turn ignition on. Measure voltage between ground and injector harness connector terminal No. 1 (Black/Red wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short circuit. See WIRING DIAGRAMS article.
- Turn ignition off. Disconnect ECM harness connector. See Figure. Check continuity of specified wire between ECM harness connector and appropriate injector harness connector. See FUEL INJECTOR CIRCUIT IDENTIFICATION (FRONTIER & XTERRA) table. See Figure. Also, check circuit for short to ground and short to voltage. Repair circuit as necessary. If circuit is okay, go to next step.
- Check fuel injector. See FUEL INJECTOR . Replace, if necessary. If injector is okay, no problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
FUEL INJECTOR CIRCUIT IDENTIFICATION (FRONTIER & XTERRA)
| Injector No. |
ECM Terminal No. |
Wire Color |
| 1 |
102 |
White/Black |
| 2 |
109 |
White/Blue |
| 3 |
104 |
White/Red |
| 4 |
111 |
White/Purple |
| 5 |
106 |
White/Green |
| 6 |
113 |
White |