Brake Lights Not Working

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mjfreshyfresh
Posts: 36
Joined: Sun Oct 27, 2013 4:21 pm

Brake Lights Not Working

Post by mjfreshyfresh » Tue Feb 17, 2015 9:59 pm

I was getting ready to hook up the "third eye" brake setup MadMax mentioned and realized my rear brake lights don't work.

What steps should I take to trouble shoot? Looks like all fuses are good, I can't find a relay that mentions "brake" in the manual.

Thanks-
MJ

dadnova
Posts: 84
Joined: Wed Jul 30, 2014 12:37 pm
Location: Nuevo, Ca.

Re: Brake Lights Not Working

Post by dadnova » Tue Feb 17, 2015 11:36 pm

Make sure the light switch is in driving mode and not military mode. I say this because my lights did not work until Edzz showed me the light switch was in military mode when I bought it.

Second I would check the bulbs for a bad ground at the lights, mine were not working some times, after wiggling the bulb it lit up, so I removed the bulbs and did a good cleaning, now I have no more issues with them.

You said you checked the fuse? What fuse as my Pinz has breakers not fuses, or is that what you meant?

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Jimm391730
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Location: Idyllwild, CA

Re: Brake Lights Not Working

Post by Jimm391730 » Wed Feb 18, 2015 12:26 am

Remember, this section is for Volvos! I've fallen into the same trap before...

I'll admit that I am not familiar with the Volvo wiring, but I'd start at the brake light switch; it is either a mechanical switch that works off the motion of the pedal or arm, or (in the case of Pinzgauers) from the pressure in the hydraulic system. But the switch is roughly half way through the circuit -- if you have continuous voltage there, and the switch closes when the pedal moves or pressure is applied, then you know the problem is somewhere between the switch and the ground at the lights. If the switch doesn't "switch" then it is bad. If the switch has no power, then the problem is somewhere between the battery and the switch (the ignition switch is usually between these).

Divide and conquer! Start in the middle, and decide which direction is the problem. Then shoot for the middle of that section and repeat.
Jim M.
712W and 710M

mjfreshyfresh
Posts: 36
Joined: Sun Oct 27, 2013 4:21 pm

Re: Brake Lights Not Working

Post by mjfreshyfresh » Wed Feb 18, 2015 9:21 am

Thanks for the info guys! Yes this is for a Volvo. ;-)

jeepboy_90
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Location: Northern California

Re: Brake Lights Not Working

Post by jeepboy_90 » Wed Feb 18, 2015 10:47 pm

MJ - under the passenger side rear wheel on the inside of the frame is the rear wiring junction box. Pop the cover off and check if you are getting power to there from the cab. The wires should all be numbered, it is super easy to just pull the rear brake light cover off, check the wire number, pop the junction box cover off and check. Also my rear lights did have fuses inside them also.

mjfreshyfresh
Posts: 36
Joined: Sun Oct 27, 2013 4:21 pm

Re: Brake Lights Not Working

Post by mjfreshyfresh » Wed Feb 18, 2015 11:02 pm

Ah thanks for the details on the electric system! It is pretty neat how they wired this thing together.

Upon closer inspection it was indeed the fuse. The contacts points were so corroded that it was making occasional contact.

I now have a functional "third eye" which makes braking way more visible. I'll post more pictures later.

Appreciate all the advice!

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