r/Eugene • u/ShastaPlaster • Nov 21 '24
Brake lights not working after doing some stereo rewiring. Any recommended auto mechanics? jiggly
Long story short - I installed a new car stereo and backup camera and part of the installation required me to strip and solder in the backup camera to a brake light on my car. That went fine, but now for some reason neither of my brake lights are working when I pump the brakes on my car.
Does anyone know a mechanic who would diagnose and/or fix this rather small and known issue on the cheaper end of things? There's not really any need for me to get anything done other than talk to someone who understands car electronics wiring and who might be able to tell me what I need to change, or do it themselves. This shouldn't be more than a $100 or so fix. I called the Stereo Store and they wanted like $800 for four hours of mechanic time which seemed like highway robbery.
Anyone have any suggestions?
4
u/Upset_Form_5258 Nov 22 '24
Not to be rude, but how could you know it should only cost around $100? What if it takes them some time to diagnose what you did wrong and actually find the problem?
3
u/SandyOwl Nov 22 '24
They are asking for an expert to help them but they only want to pay the amateur rate. Fuck that.
-1
u/ShastaPlaster Nov 22 '24
Basically I just want someone who knows something about stereo installation and wiring to take a look and tell me what's might be wrong and touch the wiring with some testers. I can basically do the fixes myself but I essentially want a second opinion before I start unsoldering stuff. I figure that's worth a C-note just to advise.
1
u/Upset_Form_5258 Nov 22 '24
Right, but someone’s time and knowledge is still valuable
1
u/ShastaPlaster Nov 22 '24
Agreed. And I think $100 is probably right in that area for what I need haha
2
u/cryotohawk Nov 22 '24
That is a good question, I didn't realize that , apologies. I had good luck there in the past.
2
u/NWGeovic Nov 22 '24
Generally speaking, I believe you're supposed to wire the backup camera (its turn on signal - metaphorically a light switch) to your reverse light signal - that way it turns on when the car is in reverse. Otherwise, wouldn't it be on whenever you put your breaks on?
When the "switch" is trigged, the camera's main power should come from an independent fused power source. Most cars have auxiliary places to accommodate this. The video signal should then go to the back of your head unit, or whatever display that you're using.
It's also possible that you wired the wrong wires together. Always look up a diagram for your specific model and year.
I would recommend you undo any wiring that you did that connected your brake lights. Do they work afterward? If yes, great, try a new approach. If not, look up the fuse # and location for your brake lights and start there. Just pull the fuse with some pliers and see if it the connection looks burnt.
1
u/ShastaPlaster Nov 22 '24
Thanks for the advice.
Some more detail - The reverse recognition is a wire goes from the harness in the dashboard to the stick shift that recognizes it when it goes into reverse, not the reverse light itself.
The backup camera's power and ground itself is soldered into the brake light housing as its power source, soldered into a black ground wire to the ground, and then the data cable is ran up front and connects to the dash monitor. I can't remember off the top of my head, I'll have to check, but which brake light and/or reverse light I soldered into. I suspect it might be the reverse light but I will check when the sun is up.
I will definitely try unsoldering and just trying the brake lights completely "raw" again to see if that resolves the issue, since if it did, that would obviously mean that the reverse camera is causing a circuit somewhere and messing up the brake lights. I also planned to check the fuse as well, though I'm not sure if that'd be it since the "always on" brake lights do work correctly during the night, it's only when the brake is pressed that they don't light up more/brighter.
2
u/NWGeovic Nov 22 '24
If you undo your solder joints (and everything works again), I suppose you could test the camera by shifting into reverse while having a long pair of jumper cables running from the camera to your car's battery. If the camera works then, you'll probably need to find an independent power source. Caution, as this connection would not be fused...
I'm not a mechanic, but anecdotally, I've had bad grounds create a current draw and then my brake lights wouldn't work. So along those lines, it could be that the camera is trying to draw too much current which inhibits your brake lights from receiving enough juice. Your car's power supply unit only provides a limited number of amps to your lights (or any individual circuit), so keep that in mind.
1
u/ShastaPlaster Nov 22 '24
I've also had that thought as well, simply not enough power to run both at the same time. I'll give these a shot and see what happens, thanks for the ideas.
1
u/PunksOfChinepple Nov 21 '24
Could you have tied a ground to the hot side of the brake lights popping a fuse? Or left the hot side exposed somewhere it could have bumped a ground or gotten wet?
1
u/ShastaPlaster Nov 22 '24
Good suggestions - It's possible I popped a fuse but I'm fairly certain that I soldered the hot to hot. It definitely didn't touch another wire or ground or get wet since it's up in the brake light housing and there's only three wires (hot, ground, brake). I was following a YouTube tutorial and they pretty clearly said to go for the red and black striped wire, and that's what I did - but you know how YouTube can be inaccurate. I would like someone to take a look at the fuses though and ideally run a connectivity test to see where there might be any fault or circuit being created.
-1
u/cryotohawk Nov 21 '24
Call Brad's Car Tunes
5
u/ShastaPlaster Nov 22 '24
Not to be a huge diva but are they the ones who have flown MAGA flags in the past? Or is that the vape shop nearby? I'm not particularly picky but that is probably the one type of business I'd like to avoid.
2
u/GrandpaTurtle Nov 22 '24
I see a house in my neighborhood flying a Trump flag and the car in the driveway has a big Brads Cartunes decal on the rear.
1
u/ShastaPlaster Nov 22 '24
Welp, that answers that question.
Anyone got any other suggestions for local places?
7
u/Embarrassed_Law_8523 Nov 22 '24
Seems like if you can install a stereo using soldering you should be able to diagnose a blown fuse, eh? I’d recommend hitting up your vehicle manual to look for fuses or consult some online forums. There’s a reason people charge a lot of money per hour to do this work, most of it is diagnostic and chasing down mystery problems caused by a current or previous owner.