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What is this? At left foot, behind brake against wall. Trying to troubleshoot wires from fuse box, going to brake light switch. I've got Red/Blue and White/black, going to
brake light switch. Red/Green is going to this Fuse 7 brake light wire is going to this, not switch. Thank you for your help!
Last edited by cdltnla; May 8, 2021 at 03:05 AM.
Reason: Need to include year make and model
Turns the cruise control off when the brake pedal is pushed. Follow the plastic pipe to the cruise control stuff under the hood. The brake light switch touches higher on the pedal arm.
Turns the cruise control off when the brake pedal is pushed. Follow the plastic pipe to the cruise control stuff under the hood. The brake light switch touches higher on the pedal arm.
Hey there, hoonk-
I think my pics weren't in the order I intended, possibly. This is the piece I'm wondering about.
Thank you for replying!
Here's the piece, circled. Thanks for your time and attention!
Last edited by cdltnla; May 9, 2021 at 01:39 AM.
Reason: correction
Mystery relay, left driver's side against wall above left foot
Originally Posted by hoonk
Looks like a relay - what are the markings on it? Are you trying to solve a problem or just want to know what that relay controls?
Hoonk- Thank you. That's what I thought, but have yet to find anything about it.
My brake lights (all) do not work.
I noticed that going into the brake switch are wires from fuse 3 and 13, which on my cover says, #3 heater fan and #13 heated seats.
Black/white & blue/red wires.
Red/green from fuse #7 (brake lights) is not going to brake switch, it's going into that relay, clustered with those other wires, rather.
I'm thinking someone got a few wires mixed up.
Thank you for paying my question attention! Much appreciated.
Thank you Hoonk-
Yes, okay, now I can see the button and I do believe I can see the green-red and blue-red wires connecting to it.
It seems to me there is a metal plate, maybe it's the steering column support, blocking it entirely. I'd like to try to access brake light switch from above by removing the instrument panel where the speedometer is. I just don't know how to remove it. (I viewed the link you provided, thank you).
Addendum: I found this video, regarding pulling out instrument panel. I may try this, just a little apprehensive about all the wires and connections.
https://m.youtube.com/watch?v=iSI8WmioK7w
Another key point is, cruise control works. Is that only controlled by the cruise control switch? At this point, I'm narrowing down. I read that if cruise control doesn't work, as well as the brake lights, then you can be sure it's a faulty bulb failure relay.
Also, tail lights (dual filament bulbs), fog lights, turn signals, headlamps and reverse lights work.
Thanks so much, again, for helping me out.
Still curious about that other relay above left foot, but that can wait.
Hope you're having a good day
P.S. I am a Mom learning this with my 21 year old son. We replaced the tail light assemblies together and are moving on
Last edited by cdltnla; May 14, 2021 at 07:27 PM.
Reason: Added info
Poor connections at the fuse, Brake light switches go bad, connections at the taillamps are always the problem. Rarely is there a cracked solder connection in the bulb out relay - but possible.
Power goes from the battery to the fuse to the switch to the bulb out relay to the taillamps (and 3rd brake light)
If you think the brake light switch is bad, just jump the two wires together and check for power at the taillamps.
Poor connections at the fuse, Brake light switches go bad, connections at the taillamps are always the problem. Rarely is there a cracked solder connection in the bulb out relay - but possible.
Power goes from the battery to the fuse to the switch to the bulb out relay to the taillamps (and 3rd brake light)
If you think the brake light switch is bad, just jump the two wires together and check for power at the taillamps.
Got it. Going to give this a go tomorrow and will follow up!
(Expand to read details on video tutorial, by clicking the upside down "V" to the right of "brake light fix"- to right of video title.)
It was the brake light switch!
Thank you for that last bit of clarification to give us the confidence to go in, Hoonk!
After months of apprehension and deducing, we nailed it with your help!
Thanks to Volvo Forums members especially senior members, Matthewsvolvosite, IPD and (YouTube) Volvo mechanic Robert Spinner.
Take time to study and label your wires and pieces!
We have brake lights!! 👍👍😄 Yeah!
Last edited by cdltnla; May 18, 2021 at 05:14 PM.
Reason: Added instructions
What is this? (1990 Volvo 240 DL)
