Camshaft Position Sensor - G40-, Checking

General Description

Using the signal from the Camshaft Position Sensor -G40-, the precise position of the camshaft relative to the crankshaft is determined very quickly when the engine is started. Used in combination with the signal from the Engine Speed Sensor -G28-, the signal from the Camshaft Position Sensor -G40- allows the Engine Control Module -J623- to detect which cylinder is at TDC. The fuel can be injected into the corresponding cylinder and ignited.

Special tools and workshop equipment required

Multimeter.
Wiring Diagram.
Scan Tool.

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: .
View clean working conditions: .

Test Procedure

NOTE:

Note the CA1 and CMC both use the ECM connector T105a, and the CA2 uses the ECM connector T105b. Both connectors are identical except for the suffix of "a" or "b". For simplicity, please use the suffix "a".

Step	Procedure	Result / Action to Take
1	PERFORM: Preliminary Check to verify the customers complaint. Refer to . -- Was Complaint verified?	-- YES: GO TO: Step 2 Camshaft Position Sensor - G40-, CHECKING - 2 . -- NO: GATHER more information from customer about the complaint.
2	IGNITION: OFF. DISCONNECT: Camshaft Position Sensor -G40- harness connector. IGNITION: ON. CHECK: Camshaft Position Sensor -G40- harness connector terminals 1 to 3 for voltage. IGNITION: OFF. SPECIFIED VALUE: About 5.0 V. -- Was Value obtained?	-- YES: GO TO: Step 3 Camshaft Position Sensor - G40-, CHECKING - 3 . -- NO: GO TO: Step 4 Camshaft Position Sensor - G40-, CHECKING - 4 .
3	REMOVE: Engine Control Module - J623-. Refer to appropriate Service Information. CHECK: Camshaft Position Sensor -G40- harness connector terminal 2 to the Engine Control Module - J623- harness connector T105a / 89 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Was Value obtained?	-- YES: REPLACE: Camshaft Position Sensor -G40-. Refer to appropriate Service Information. GO TO: Step 5 Camshaft Position Sensor - G40-, CHECKING - 5 . -- 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 5 Camshaft Position Sensor - G40-, CHECKING - 5 .
4	REMOVE: Engine Control Module - J623-. Refer to appropriate Service Information. CHECK: Camshaft Position Sensor -G40- harness connector terminal 1 to the Engine Control Module - J623- harness connector T105a / 54 for resistance. CHECK: Camshaft Position Sensor -G40- harness connector terminal 3 to the Engine Control Module - J623- harness connector T105a / 59 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Were Values obtained?	-- YES: GO TO: Step 5 Camshaft Position Sensor - G40-, CHECKING - 5 . -- 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 5 Camshaft Position Sensor - G40-, CHECKING - 5 .
5	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 Service Information. Clear the DTC's. Refer to . Repair is complete. Generate Readiness Code. Refer to . 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.