REVERSE LIGHTS NO POWER

[stgunsman1]

We have a Landrover Disco 3, and we decided to put some spot lights onto
our roof rack at the rear of the vehicle.
We connected the wires of the spotlights to the reverse lights so when we put it in reverse the spotlights would come on automatically. it worked fine for a couple of days and the fuse blew in the passenger side glove box.
Went fine for another couple of days and then stopped working, fuse is okay.
Is there a switch on the transmission somewhere that controls reversing lights.

Help on this subject would be appreciated.

Cheers
Tim

[bbyer]

The reverse lamps are active when the ignition switch is in the ignition position (II) and the CJB receives a reverse selected signal on the CAN bus. Both manual and automatic transmissions have a reverse switch which senses when reverse is selected.


I looked at the electrical diagram and I see a reverse switch referenced with the inferred location of it being somewhere near the "gearbox", whatever that means.


I assume the fuse you replaced was a 10 amp call 5P for fuse #5 located behind the lower interior glove box door. That fuse protects what is called a FET, Field Effect Transistor, that is in effect a solid state relay melted into a printed circuit board located behind the fuses. One hopes that is still OK as it cannot be replaced separately - you need a whole new circuit board and that is a big deal.


The short story is once you get the reverse lights working again, use the circuit to power a relay for your aux rear lights. If you got away with it this time with only a reverse switch problem, be happy.


If it is the reverse switch, let us know where it is located and what it looks like. While hopefully it is some sort of electro mechanical thing like the brake light switch, I fear it may instead be some electronic circuit board with no moving parts kind of integrated into the transmission shift electronics. The electrical drawing shows four conductors going into it coming off what is called a Transfer Box control module.