The throttle potentiometers represent an integral part of the electric throttle valve actuator EDK (refer to ”Electric throttle valve actuator”). They serve the purpose of detecting the current position of the throttle valve.
The electric throttle valve (EDK) is adjusted with a DC motor and a gear unit. The position of the throttle valve is detected by means of a double potentiometer that is mounted on the throttle valve shaft and which rotates in the opposite direction.
Corresponding to the position of the throttle valve, the voltage signals for potentiometer 1 are between 0.5 V and 4.5 V and opposingly for potentiometer 2 between 4.5 V and 0.5 V.
The following monitoring functions are realized in the DME control unit for the throttle potentiometers:
- Monitoring of both potentiometers for electrical faults
- Potentiometer 1 is a control potentiometer
- Potentiometer 2 is a reference for potentiometer 1
- Plausibility monitoring of both potentiometer signals with respect to each other
If a fault occurs during operation a corresponding fault code will be stored in the fault code memory of the DME control unit.