2004 Volvo XC70 Brake Lights Stuck On

tyguy · Post by **tyguy** » 10 Jul 2020, 15:56

Hi there,

I am new to the forum and car repairs in general, but like to avoid taking my car into the shop when possible...

Anyways, the brake lights on my 2004 Volvo XC70 recently started sticking on, even after the car is turned off. I didn't notice at first and was greeted with a dead battery.

After doing some initial research on the forums, I figured that the problem is most likely the brake light switch. I inspected the switch and it did look like it might be the issue - it was not being fully compressed when I took my foot off the brake and the brake pedal felt ever so slightly "loose" (when released you can play with it by hand and it will wiggle a tiny bit up and down). I tried fully compressing the brake light switch by hand, but the brake lights stayed on. I also unplugged the brake light switch altogether and that too had no effect, the lights stayed on.

One strange part that has me stumped is the 3rd brake light across the top middle does not stay on with the others, but it does turn on and seem to work fine when the brake pedal is depressed (and then goes off again when released, while the side brake lights remain on).

So far, I've been able to work around the problem by jiggling the brake pedal a bunch until the lights finally turn off. I ordered a new brake light switch online but am not convinced that it will solve my problem.

Any help or advice would be greatly appreciated!

-Ty

Post by **darrylrobert** » 10 Jul 2020, 20:13

i would say its your brake switch, the LED draws less current than the lower incandescent bulbs so that may explain it..not sure

Post by **oragex** » 11 Jul 2020, 03:32

Careful when removing/adjusting that switch, there is a video on yt.
If my memory still works, the lower brake lights are controlled by the REM (google up) while the upper one is by the CEM
Possibly there is a faulty relay in the REM, it appears to be RM15 or RSH6
viewtopic.php?t=37819
https://volvoforums.com/forum/volvo-s80 ... ram-17196/

Post by **chrism** » 11 Jul 2020, 15:52

As I recall there is only one circuit that passed through brake light switch so it “seems” improbable that the switch could partially fail in a way that it continues to illuminate the higher amperage bulbs and not the low amp LEDs. Did you check the switch open/close function with an ohm meter (with wires disconnected).