Genuine Volkswagen Passat Brake Light Switches

Volkswagen Passat Brake Light Switches Parts and Q&A

• Parking Brake Warning Switch
  1H0-947-561-A
  Q: What are the locations of brake light switches and how can they be accessed and tested on Volkswagen Passat?

  A:

  The brake light switch is on the bracket of the pedal on which the brake pedal is mounted and it is situated near the top and once the pedal is depressed the brake lights are switched on. The knee bolster and left side under-dash panel have to be removed to reach the switch. The fuse should be checked in case the brake lights are not on. In the case of an intact fuse, then the voltage on the switch on the feed wire is to be checked, and in the event of no voltage, the conduit between the switch and the fuse box must be repaired. In case of the presence of voltage, the terminal of the output wire must be tested when the brake pedal is pressed; in case no voltage is detected, the switch must be changed. Voltage at the output is expected to also indicate power on the brake light wires at the tail light housings, when the brake pedal is depressed: in the event that there is no voltage, the circuit between the switch and the brake lights must be repaired. A bad ground is to be tested by probing at the tail light connector, the ground wire terminal with a jumper wire to a good ground, and in case the brake lights go on, the ground circuit is faulty. Another point to be taken into consideration is the fact that the brake light bulbs might be burnt, but the possibility that all bulbs will go dead at the same time is low. To adjust, thread the switch in or out to provide a clearance of around 1/64-inch (0.4 mm) between the end of the switch body and the plunger pointing out that to adjust some models may involve loosening a locknut or working with a pressed-metal nut. To replace, the under-dash panel on the left-side and knee bolster will be pulled out, the electrical connector de-plugged, the switch unscrewed to the bracket, without forgetting the pressed-metal nut (where present). The old switch has a locknut, which should be transferred to the new one. The new switch is then fitted by reversing the 3 steps of removing and then setting the switch and then reconnecting with the electrical connector and then testing the work of brake light and then installing the knee bolster and under-dash panel again.