Fuel Pressure Regulator Valve, Checking
Fuel Pressure Regulator Valve, Checking
The following test procedure is used to diagnose the fuel pressure regulator valve.
Electrical Test
Special tools, testers and auxiliary items required
• Multimeter.
• Wiring diagram.
Test requirements
• The ECM Power Supply Relay (J271) fuses OK.
• The Battery voltage at least 12.5 volts.
• All electrical consumers such as, lights and rear window defroster, switched off.
• Vehicles with automatic transmission, shift selector lever into position " P" or "N".
• A/C switched off.
• Ground (GND) connections between engine/transmission/chassis OK.
• Ignition switched off.
Test procedure
- Perform a preliminary check to verify the customers complaint. Refer to --> [ Preliminary Check ] Preliminary Check
Start diagnosis
- Observe safety precautions.
- Observe rules for cleanliness.
- Disconnect the Fuel Pressure Regulator Valve electrical harness connector from Fuel Pressure Regulator Valve (N276).
Checking internal resistance
- Using a multimeter, check the Fuel Pressure Regulator Valve electrical terminals 1 to 2 for resistance.
Specified value: 12.0 to 20.0 ohms (at approx. 20° C)
If the specified value was not obtained:
- Replace the Fuel Pressure Regulator Valve, N276..
If the specified value was obtained:
Checking activation and wiring
- Using a multimeter, check the electrical harness connector terminals 1 and 2 of N276
If the manufacturers test box is being used. Perform the following step.
- Install the test box.
If the manufacturers test box is not being used. Perform the following step.
- Remove the Engine Control Module (ECM) (J623).
- Turn Key On
- Measure Pin 1 of Fuel Pressure Regulator Valve harness connector to Ground (GND)
- Measure Pin 2 of Fuel Pressure Regulator Valve harness connector to Batt +.
- Specified value: 12.5 Battery V
- If the specified value was not obtained:
If the manufacturers test box is being used. Perform the following step.
- Install the test box.
If the manufacturers test box is not being used. Perform the following step.
- Remove the Engine Control Module (ECM) (J623).
- Using a Multimeter, check the Fuel Pressure Regulator Valve electrical harness connector terminals to the Motronic Engine Control Module (ECM) (J623) electrical harness connector T60 terminals for an open circuit.
Specified value: 1.5 ohms Max
If the specification is not obtained:
- Check the wiring for a short circuit to each other, Battery (+), and Ground (GND).
- Check the electrical harness connector for damage, corrosion, loose or broken terminals.
- If necessary, repair the faulty wiring connection.
- Erase the DTC memory. Refer to --> [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Mode 04 - Erase DTC Memory
- Perform a road test to verify repair.
If the DTC does not return:
Repair complete, Generate readiness code. Refer to --> [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.
- End diagnosis.
If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK:
- Replace the Motronic Engine Control Module (ECM) (J623).
- Assembly is performed in the reverse of the removal.
Final procedures
After repair work, the following work steps must be performed in the following sequence:
1. Check the DTC memory. Refer to --> [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Mode 03 - Read DTC Memory.
2. If necessary, erase the DTC memory. Refer to 3.6 Liter V6 4V Engine Mechanical, Fuel Injection & Ignition, Engine Code(s): BHL, BHK--> [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Mode 04 - Erase DTC Memory.
3. If the DTC memory was erased, generate readiness code. Refer to --> [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.
- End of diagnosis.