Instrument Cluster

TROUBLESHOOTING

Notes

Troubleshooting mainly takes place in accordance with the instructions provided by the BMW DIAGNOSTIC SYSTEM. Note information provided on the screen displays!

Configuration of Defect Pages on the Display Screen

*D* Defect evaluation

The defect "EGS signal line faulty", "oil temperature sensor voltage not plausible" and "internal voltage supply faulty" can only be evaluated as of software status >15.0.

The software status of the instrument cluster can be read out via *D* identification.

Defect Numbering

Defect numbering involves consecutive numbering of all defect texts.

Defect Code Identification

The defects are identified as "defect current" or "defect not current". The display "defect current" means that the defect was detected after switching on the ignition or during driving.

The display "defect not current" means that the defect was detected at least once since the last time the defect memory was cleared but has not occurred again since the last time the ignition was switched on or while driving.

How often the defect has been detected cannot be read out.

Types of Defect

Four different types of defect are detected.

- "Short to plus"
- "Short to minus"
- "Break"
- "Operating range exceeded"

Not every defect can be detected with each type of defect. Detection of the type of defect differs depending on the defect itself (sensor, memory module, measuring instruments etc.)

The type of defect "short to plus" means that a connection to battery plus has been detected at the component marked as being defective or at the corresponding output or input.

The term "plus" may refer to the plus of the vehicle electrical system or a plus generated internally by the instrument cluster. The type of"plus" is indicated in the schematics.

The type of defect "short to minus" means that a connection to minus has been detected at the component marked as being defective or at the corresponding output or input.

The type of defect "break" means that a break in the connection has been detected at the component marked as being defective or at the corresponding output or input.

The type of defect "operating range exceeded" means that the operating range has been exceeded at the component found to be defective or at the corresponding output or input.

Example of Type of Defect "Operating Range Exceeded"





When the ignition is switched on, the voltage divider of the control unit supplies a voltage at the sensor output.

The temperature-dependent resistor in the sensor changes its resistance dependent on the temperature. This change in resistance causes a change in voltage at the voltage divider of the control unit.

This voltage is converted by the control unit into a temperature value and further processed. The voltage value which the sensor can take up during trouble-free operation is compared to the stored limit values by the control unit. A defect is detected if the values are above or below the limit values.