Conditions

Rheostat. Open-circuit





Fault symptoms
The lighting controlled by the rheostat is on full continuously. The rheostat does not work.

Condition
A resistance higher than 1250 ohms generates a diagnostic trouble code.

Diagnostic help
The rheostat and rheostat level can be read using the diagnostics tool. The rheostat should be between 0 V and 3.5 V and the rheostat position should correspond to this.

The rheostat level sent out on the bus should be 25-100% when the headlamps are ON.

Check the wiring harness
Jiggle the wiring harness at several points and in different directions to detect intermittent breaks and short-circuits in the leads. Observe the multimeter, test lamp or diagnostics instrument during the test.