Fuel Pump Control Module (J538)

Fuel Pump Control Module (J538)

Special tools, testers and auxiliary items required

• Fuel Tank Sender Unit Tool (T40068 A)

Removing

- Follow all safety precautions. Refer to => [ Safety Precautions ] Safety Precautions.

- Follow the guidelines for clean working conditions. Refer to => [ Clean Working Conditions ] Clean Working Conditions.

Danger due to escaping fuel.

• To prevent large quantities of fuel from draining from the Fuel Pump (FP) control module when removing, the fuel tank may only have a maximum of 1/4 full.

- Empty the fuel tank if necessary. Refer to => [ Fuel Tank, Draining ] Procedures.

- Move the passenger seat all the way forward if necessary.

Danger of causing damage to other electronic components when disconnecting the battery.

• Complete the steps for disconnecting the battery.

- Disconnect the battery.

- Remove the rear seat bench.






- Remove the locking flange cover - arrows -.

- Disconnect the connectors - 1 and 2 - on the locking flange.






- If necessary, disengage the electrical connector - 3 - to the auxiliary heater metering pump at the locking flange and lay it aside.








There is a risk of injury because the fuel is under high pressure.

• To reduce pressure in fuel system, lay a clean cloth around the connector and carefully loosen connector.

- Disconnect the fuel line - 2 - at the locking flange by pressing the release button.

- If necessary, disconnect the fuel line - 1 - to the auxiliary heater metering pump at the locking flange by pressing the release button.








Danger due to escaping fuel.

• To prevent large quantities of fuel from leaking out of the locking flange when removing, the fuel tank may only be a maximum of 1/4 full.

- Use a (T40068 A) to remove the union nut - arrow -.

• When union nut is loosened, plastic catch on threaded ring breaks off - ignore.

- Cover the fuel tank opening with a clean cardboard box - 1 - to prevent dirt from falling into it.






- Remove the bolts - arrows -.

- Pull the FP control module - 1 - in between the fuel tank and vehicle underbody.






- The control module must be guided between the floor panel and the fuel tank. Sometimes it is necessary to lift the floor panel slightly in order to do this (on case by case basis).

- Disconnect the connector and remove the FP control module.

Installing

• Tightening specification, refer to => [ Fuel Delivery Unit and Fuel Level Sensor Overview ] Fuel Delivery Unit and Fuel Level Sensor Overview.

Install in reverse order of removal. Note the following:

• Replace the sealing ring and the union nut.

- Bring the FP control module into installation position and tighten it.

- Place the union nut - 1 - on your left arm and push the locking flange - 2 - forcefully into installation position with your left hand - arrow -.






• The tab - 4 - on locking flange must lie between tabs - 3 and 5 - on threaded ring.

- Slide the union nut - 1 - off your left arm using your right hand while your left hand keeps holding the locking flange - 2 - down firmly - arrow -.






- Position the union nut - 1 - with your right hand so the double ridge - 5 - on the ribs is over the lug - 3 - on the locking flange (approximately "10 o'clock" position). This makes sure the union nut engages at the beginning of the threads immediately when tightening it - 4 -.

- Press the locking flange down firmly with a screwdriver - arrow -.






- Turn the union nut approximately 480° with your right hand until the double ridge - 1 - is in approximately "2 o'clock position" while keeping the locking flange pressed down firmly with your left hand.








There is a risk of the locking flange threaded connection leaking.

• Press the locking flange down firmly when tightening the union nut so it does not rotate too.

- Tighten the union nut using (T40068 A).

• Verification: The double ridge - 1 - must now be between "7 and 8 o'clock".






- Connect fuel lines - 1 and 2 -.






- Connect the connectors.

- Install the right locking flange cover. Refer to => [ Locking Flange Cover - Tightening Specifications ] Fuel Tank With Attachments Overview.

- Install the rear seat bench.

- Connect the battery. Be sure to read the procedures after connecting the battery.

- Vehicles with auxiliary heater: To vent the fuel line to the auxiliary heater metering pump, run for 10 minutes at wide open throttle.