Low Fuel Pressure Sensor G410, Checking

Low Fuel Pressure Sensor G410, Checking

Special tools, testers and auxiliary items required
- Multimeter
- wiring diagram

Test requirements
- Fuel Pump (FP) Control Module J538 OK; check.
- The fuel filter OK.
- The fuses for the engine electronics OK.
- The parking brake engaged.
- The battery voltage at least 12.5 V.
- The selector lever of automatic transmission in position "P" or "N".
- All electrical consumers switched off (radiator fan must NOT run during test).
- A/C switched off.
- The fuel tank at least 1/4 filled.
- The ignition switched off.

Test procedure
- Perform a preliminary check to verify the customers complaint. Preliminary Check

Start diagnosis

Procedure







- Remove engine cover - arrows -.

Checking voltage







- Disconnect the electrical harness connector - 2 - from the Low Fuel Pressure Sensor G410.
- Switch the ignition on.







- Using a Multimeter, check the electrical harness connector for voltage.

Harness connector Terminal Specified value
1 to Battery positive (+) Battery positive (+)
2 to Ground (GND) Battery positive (+)
3 to Ground (GND) about 5 V

- Switch the ignition off.

If specified value is obtained:
- Replace the Low Fuel Pressure Sensor G410

If the specified value was not obtained:

Checking wiring connections
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 Motronic Engine Control Module (ECM) J623.

Low Fuel Pressure Sensor Motronic Engine Control Module (ECM)
G410 electrical harness J623 electrical connector T60 terminals
connector terminals or T94 or test box sockets
1 14
2 15 of T94
3 37

Specified resistance 1.5 Ohms max.

If the specification is not obtained:
- Check the wiring for a short circuit to Battery positive (+) or an open circuit.
- If necessary, repair the wiring connection.
- Erase the DTC memory. Diagnostic Modes 01 - 09
- Perform a road test to verify repair.

If the DTC does not return:
Repair complete, Generate 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 mentioned sequence:

1. Check the DTC memory. Diagnostic Modes 01 - 09
2. If necessary, erase the DTC memory. Diagnostic Modes 01 - 09
3. If the DTC memory was erased, generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes

End of Diagnosis