Exhaust Pressure Differential Sensor: Service and Repair

Differential Pressure Sensor G505

• The differential pressure sensor determines the particulate filter load level. The 2 wires can be connected in front of and behind the particle filter, or if there is only one wire, in front of the particle filter. In this case, the pressure sensor measures the ambient pressure with an open wire and calculates the pressure difference.

Component location, refer to => [ Front Exhaust Pipe with Particulate Filter Overview ] Front Exhaust Pipe with Particulate Filter Overview.

Removing

- Remove the engine cover. Refer to => [ Engine Cover ] Engine Cover.

- Remove the coolant expansion tank bolts - 3 -.






- Disconnect and remove the connector from the coolant expansion tank - 2 -.

- Lay the coolant expansion tank - 2 - on the engine.

Very hot fuel can burn your skin.

• The temperature of the fuel lines and may reach 100 °C (212 °F) after stopping the engine. Allow the fuel cool down before opening any line connections otherwise there is a danger of scalding.

• Wear protective gloves.

• Wear safety glasses.

- Disconnect the fuel line couplings - A and B - and remove the fuel lines.






- Unclip the fuel lines on the differential pressure sensor bracket.

- Release and disconnect the connector - 2 - from the differential pressure sensor.






- Remove the bolt - 4 -.

- Remove the screw - 3 -.

- Remove the differential pressure sensor from the bracket.

- Remove the bolts - 1 - and remove it from the bracket.

- Remove the clamps on both hoses.

- Pull the hoses straight off the connections to remove. The connections break off of the pressure sensor very easily.

Installing

Install in reverse order of removal. When doing this note the following:

• Before installing, clean the control lines leading from the differential pressure sensor to the particulate filter with compressed air to make sure they are not plugged or iced over with condensation.

• Check for secure fit and leaks.

• In case the particulate filter pressure lines were loosened, tighten the pressure lines, refer to => [ Front Exhaust Pipe with Particulate Filter Overview ] Front Exhaust Pipe with Particulate Filter Overview.

An adaptation must be performed after replacing the differential pressure sensor and/or particulate filter. The procedures are also described in Guided Fault Finding.

Enter the correct vehicle into Guided Fault Finding.

- Press the "GO TO" button.

- Select "Function/component selection".

- Select "drive".

- Select engine code.

- "01 - On Board Diagnostic (OBD) capable systems"

- Select "01 - Diesel Direct Injection- and Preglow System EDC 17".

- Select "01 - Functions".

- Select "01 - reset adaptation value for differential pressure sensor for diesel particulate filter".

Tightening Specifications