Code 12 (Throttle Position Sensor)

Defect Code 12

•D•1 Defect code memory: 12 Throttle potentiometer:

Explanation: This defect code is stored when a break or shorts occur at the throttle potentiometer or on its supply wires.

Effects of defect:

- Increased idle speed

- Restricted operation, delayed reaction to accelerator pedal operation and loss in performance

Troubleshooting: Check throttle potentiometer with •D•2 Status monitoring. Press accelerator pedal and observe throttle value, idle, part load and full load signals. The voltage value must increase uniformly when the accelerator pedal is depressed.

The idle setting of the throttle potentiometer must be detected as the idle speed. In the case of automatic transmission, full load must be detected just before the kick-down.

If not: Disconnect DME control unit. The control unit then relearns the throttle idle voltage.