Fuel Pressure Regulator Valve - N276-, Checking

General Description

The Engine Control Module -J623- regulates the Fuel Pressure Regulator Valve -N276- directly at the high pressure fuel pump to control the low pressure valve inside the high pressure fuel pump.

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 Fuel Pressure Regulator Valve - N276-, CHECKING - 2 . -- NO: GATHER more information from customer about the complaint.
2	IGNITION: OFF. DISCONNECT: Fuel Pressure Regulator Valve -N276- harness connector. CHECK: Fuel Pressure Regulator Valve -N276- component connector terminals 1 to 2 for resistance. SPECIFIED VALUE: 1.0 - 11 Ω (+/- 0.5 Ω @ approx. 20° C). -- Was Value obtained?	-- YES: GO TO: Step 3 Fuel Pressure Regulator Valve - N276-, CHECKING - 3 . -- NO: REPLACE: Fuel Pressure Regulator Valve -N276-. Refer to appropriate Service Information. GO TO: Step 4 Fuel Pressure Regulator Valve - N276-, CHECKING - 4 .
3	REMOVE: Engine Control Module - J623-. Refer to appropriate Service Information. CHECK: Fuel Pressure Regulator Valve -N276- harness connector terminal 1 to the Engine Control Module - J623- harness connector T105a / 43 for resistance. CHECK: Fuel Pressure Regulator Valve -N276- harness connector terminal 2 to the Engine Control Module - J623- harness connector T105a / 44 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Were Values obtained?	-- YES: TIP: The Fuel Pressure Regulator Valve -N276- may fail under loaded operation; please swap a known good Fuel Pressure Regulator Valve -N276- prior to continuing to the next step. GO TO: Step 4 Fuel Pressure Regulator Valve - N276-, 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 Pressure Regulator Valve - N276-, 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 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.