On Mercedes-Benz vehicles equipped with turbochargers or superchargers, check engine lights may come on if the wastegate solenoid fails or if there is a wire harness issue.
- Check engine light on
- Loss of power
- Bost limited exceeded or reduced.
- Warning message on dashboard
Related fault codes P0243, P0244, P0250, P0245, P0246.
Wastegate boost pressure control solenoid sometimes may be referred to as boost bypass solenoid.
In addition to the turbocharger/supercharger wastegate solenoid, the problem could also be:
- damaged wires
- short to ground
- bad connector
- corroded contacts
- defective ECU
What you will need
- Park your Mercedes-Benz on level ground and allow the engine to cool down.
- Set the parking brakes, then pull the hood release under the dashboard to open the hood.
- Remove the air intake pipe. Twist the plastic screw to unlock the plastic screw. Then pull away from the intake pipe.
- Disconnect the electrical connector from the wastegate solenoid. First, you will need to release the small locking tab the pull on the connector.
Verify that power is going to the solenoid. Use a digital multimeter to check if there is a 12 volt going to the solenoid. Rember to turn on the ignition when you check the voltage.
- Remove all bolts that secure the waste solenoid to the engine block. In this case, we have three bolts that need to be removed with a 5mm Allen key.
- Remove the wastegate solenoid from the engine.
- Install the new Turbocharger/Wastegate control solenoid valve. Make sure the O ring or gasket is seated properly.
- Thread all the bolts by hand, then torque to 14 ft-lb.