Low Fuel Pressure Sensor - G410-, Checking

General Description

The low side fuel pressure is constantly measured by the Low Fuel Pressure Sensor -G410- and sent to the Engine Control Module -J623-. If this pressure deviates from the desired pressure, the Engine Control Module -J623- sends a signal to the Fuel Pump Control Module -J538-. The Fuel Pump Control Module -J538- then sends a PWM signal to the Transfer Fuel Pump -G6- until the desired fuel pressure is achieved.

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: SAFETY PRECAUTIONS .
View clean working conditions: 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 PRELIMINARY CHECK . -- Was Complaint verified?	-- YES: GO TO: Step 2 Low Fuel Pressure Sensor - G410-, CHECKING - 2 . -- NO: GATHER more information from customer about the complaint.
2	IGNITION: OFF. DISCONNECT: Low Fuel Pressure Sensor -G410- harness connector. IGNITION: ON. CHECK: Low Fuel Pressure Sensor -G410- harness connector terminals 1 to 2 for voltage. IGNITION: OFF. SPECIFIED VALUE: About 5.0 V. -- Was Value obtained?	-- YES: GO TO: Step 3 Low Fuel Pressure Sensor - G410-, CHECKING - 3 . -- NO: GO TO: Step 4 Low Fuel Pressure Sensor - G410-, CHECKING - 4 .
3	REMOVE: Engine Control Module - J623-. Refer to appropriate Service Information. CHECK: Low Fuel Pressure Sensor -G410- harness connector terminal 3 to the Engine Control Module - J623- harness connector terminal T105a / 33 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Was Value obtained?	-- YES: REPLACE: Low Fuel Pressure Sensor -G410-. Refer to appropriate Service Information. GO TO: Step 5 Low Fuel Pressure Sensor - G410-, 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 Low Fuel Pressure Sensor - G410-, CHECKING - 5 .
4	REMOVE: Engine Control Module - J623-. Refer to appropriate Service Information. CHECK: Low Fuel Pressure Sensor -G410- harness connector terminal 1 to the Engine Control Module - J623- harness connector terminal T105a / 32 for resistance. CHECK: Low Fuel Pressure Sensor -G410- harness connector terminal 2 to the Engine Control Module - J623- harness connector terminal T105a / 11 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Were Values obtained?	-- YES: GO TO: Step 5 Low Fuel Pressure Sensor - G410-, 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 Low Fuel Pressure Sensor - G410-, 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 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.