کلید چراغ دنده عقب معیوب

The switch reporting that reverse is selected, faulty. On a manual transmission it is a simple mechanical switch in the gearbox casing, and it does more than light the lamps — reversing cameras, parking sensors and some driver assistance systems act on it.

The symptom is reversing lamps that do not work, and on a modern vehicle a camera that never appears. Its position is what fails it: threaded into the casing, exposed to road spray and salt underneath, so a corroded connector is likelier than a failed switch. Test at the connector with reverse selected — that separates switch from harness in one measurement, and a switch weeping oil around its threads has failed its seal and is usually failing electrically too.