Fuel Injectors, Checking

General Description

The Fuel Injectors -- are controlled by the Engine Control Module -J623- and are mounted normally in the cylinder head. The fuel injectors spray high-pressure atomized fuel directly into the combustion chamber.

Special tools and workshop equipment required

Multimeter.
Wiring Diagram.
Scan Tool.
LED Test Lamp.

Test requirements

Fuses OK.
Battery voltage OK.
Switch OFF all electrical and electronic accessories.
Vehicles with automatic transmission, ensure the selector lever position is in "P".
Vehicles with manual transmission, ensure the shifter lever position is in "N" with the parking brake applied.
Observe all safety precautions: SAFETY PRECAUTIONS .
View clean working conditions: CLEAN WORKING CONDITIONS .

Test Procedure

Step	Procedure	Result / Action to Take
1	PERFORM: Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK . -- Was Complaint verified?	-- YES: GO TO: Step 2 FUEL INJECTORS, CHECKING => 2 . -- NO: GATHER more information from customer about the complaint.
2	IGNITION: OFF. DISCONNECT: Suspect Fuel Injector -- harness connector. CHECK: Suspect Fuel Injector -- component connector terminals 1 to 2 for resistance (refer to appropriate wiring diagram for correct terminal and connector locations). SPECIFIED VALUE: 0.5 - 15 Ω (@ approx. 20° C). -- Was Value obtained?	-- YES: GO TO: Step 3 FUEL INJECTORS, CHECKING => 3 . -- NO: REPLACE: Suspect Fuel Injector -- (s). Refer to appropriate repair information. GO TO: Step 4 FUEL INJECTORS, CHECKING => 4 .
3	REMOVE: Engine Control Module - J623-. Refer to appropriate repair information. CHECK: Suspect Fuel Injector -- harness connector terminal 1 to the Engine Control Module - J623- harness connector T60 / xx for resistance (refer to appropriate wiring diagram for correct terminal and connector locations). CHECK: Suspect Fuel Injector -- harness connector terminal 2 to the Engine Control Module - J623- harness connector T60 / xx for resistance (refer to appropriate wiring diagram for correct terminal and connector locations). SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Were Values obtained?	-- YES: TIP: The Fuel Injector -- may fail under loaded operation; please swap a known good Fuel Injector -- prior to continuing to the next step. GO TO: Step 4 FUEL INJECTORS, CHECKING => 4 . -- NO: PERFORM: Visual Inspection of wiring and component. CHECK: Wiring for open, high resistance, short or harness connector for damage, corrosion, loose or broken terminals. REPAIR: Faulty wiring or connector. GO TO: Step 4 FUEL INJECTORS, CHECKING => 4 .
4	Final Procedure Perform a road test to verify repair. -- Does the original DTC return?	-- YES: CHECK: Engine Control Module -J623- harness connector for any damaged, pushed-out pins. REPAIR: As necessary. If all electrical connections are OK: REPLACE: Engine Control Module -J623-. Refer to appropriate repair information. Clear the DTC's. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY . Repair is complete. Generate Readiness Code. Refer to READINESS CODE . Return vehicle to Customer. -- NO: Perform the diagnostic procedure for any DTC's. If no DTC's return, the repair is complete. Return vehicle to customer.