Mechanics

BRAKE LIGHTS

2001 Volvo S80

Brakes problem
2001 Volvo S80 6 cyl Front Wheel Drive Automatic 115000 miles

I have tested all of the bulbs on my trunk brake lights, all test positive that they have not burned out. I have examined the fuses that operate the brake lights in the trunk of the car, and they do not need replacement. So what could be wrong? My back up lights work, and my turning signal lights work in the rear of the car, but my brake lights do NOT work except for the one in the rear windshield. I THINK it might be the module, but not sure. Can you confirm? I am a single Mom - and do not have extra money to diagnose the problem. On my last visit to Volvo, only my position lights in the rear were " out", now it is all brake lights except directional and back up lights. Any ideas? Any ideas on cost?
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Petsitter711
May 6, 2009.



Most likely problem is going to be your brake light relay that has gone bad. The relay is located on the rear electronic module located in the trunk behinde the left side cover. Check fuse #3 15A to make sure it is ok. Use a simple test light to make sure there is power going through it as well. If fuse is good replace the relay. If you look closely you will see a letter with a number. Look for RMI5 that is your relay that conrols your left and right side brake lights. You can swapp out the relay for the one above it just to test it really quick. Now if for some reason that is not the problem then also look at the very thin chips above the relay. Those are called shunts. I may have seen only one go bad but would not rule that out as well. The number location for that is RSH6. But like I mentioned before more probable cause is the relay. From reading your post it looks like you already now what you are doing so just pick up the relay yourself and install it if it ends up being bad. Good luck and hope this long post was not confusing. If you have any other questions just ask and I will try to answer it the best I can.

JIS001
May 7, 2009.
Thank you for your comments/help. My Volvo dealer has indicated to me that the replacement part is an electronic brake module that needs to be installed ONLY by the dealer since " software" is required to install it - to the tune of $625! I am not sure if they are taking me for a ride or what? $625 seems like a lot of money for a computer module.

Tiny
Petsitter711
May 7, 2009.
I do not see how the Brake Control Module would effect your brake lights since the lights are tied into the Rear Electronic Module. Swapp out the relay and check the brake lights. If that does not work swapp out the shunt. And see what happens. I posted the locations on the first post.

JIS001
May 7, 2009.