Fuel Injector System Test
NOTE:
A fault in fuel injector circuit may set Code 51 or DTC P0170. To test system, see CODE 51 or DTC P0170 diagnostic procedures in the TESTS W/CODES
article.
- Turn ignition off. Disconnect injector harness connectors (left and right banks). Disconnect ECM harness connector. Turn ignition on. Measure voltage between ground and each injector harness connector Yellow wire.
- Also measure voltage between ground and ECM harness connector terminal No. 109 (Red/Black wire). Battery voltage should be present. If battery voltage is present, go to next step. If battery voltage is not present, check 25-amp fusible link located in fusible link box next to battery. If fusible link is okay, repair or replace harness or connectors.
- Turn ignition off. Check continuity between ECM harness connector terminals No. 101 (Green/Orange wire), No. 103 (Green/Red wire), No. 105 (Yellow/Green wire), No. 110 (Green wire), No. 112 (Yellow/Purple wire) and No. 114 (Gray/Blue wire) and corresponding fuel injector harness connector wire color. Continuity should exist.
- If no continuity, repair or replace harness or connectors. If continuity exists, check fuel injector. See FUEL INJECTOR . If fuel injector is okay, check ECM terminals, harness, and connector terminals for damage or corrosion. Repair or replace as necessary.