Oil temperature gauge

On the M-models, an oil temperature gauge is used in the instrument cluster instead of the fuel consumption indicator.

The oil temperature displayed in the instrument cluster is determined by a model that is based on the coolant temperature at the cooler outlet, the oil temperature from the oil level transmitter, the coolant temperature of the engine, the ambient temperature and the intake-air temperature.

Procedure in the event of a fault:

1. Check the instrument cluster

Run a self-test of the instrument cluster.

For the self-test of the instrument cluster, check whether the oil temperature gauge behaves correctly. If it does not, the instrument cluster must be replaced.

2. Check the thermal oil level transmitter

If the oil temperature gauge is defective with the additional Check Control message ”Check engine oil level”, proceed as follows:

• Check the power supply and earth connection for the oil level transmitter
  
• Check the cable from the oil level transmitter to the DME control unit and to the instrument cluster
  
• If necessary, replace the oil level transmitter
  

If the oil temperature gauge is defective without the additional Check Control message ”Check engine oil level”, proceed as follows:

• In the control unit functions for the DME digital engine electronics, select the oil temperature gauge and check whether the displayed engine oil temperature corresponds to the oil temperature in the engine.
  
• In the event of a fault, replace the oil level transmitter.
  

3. Check the coolant-temperature sensor/exit of the recirculated air/intake air sensor:

• In the control unit functions for the DME digital engine electronics, select the oil temperature gauge and check whether the displayed sensor values correspond to the temperature values in the engine.
  
• Check the cable from the DME control unit to the sensor
  
• If necessary, replace the defective sensor.