When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I have a question about the Brake Lamp Sensor also that I saw some good replies from you, Jim, on when I searched it. Now that the brakes are all good would be nice not to see that Brake Lamp light on the dash. I fully understand from reading this is not related to the Brake system and functions only to alert you to the Brake Lamps being out. I did not expect it to go out when the brakes were repaired.
It has been on since we purchased the car almost a month ago now. I understand the sensor works with the lights acting as ground. Jim, I followed your instruction from some of those threads to try replacing ALL bulbs. The idea there being that some may be about to go out though visibly working and be interrupting the circuit. It was still on. It went off once randomly in the middle of a drive when I looked down, but then was back on again a few miles down the road. And never off again.
I located the brake sensor and disconnected the plug, rudimentarily cleaning with alcohol. No change. I saw instructions here https://www.hondaaccordforum.com/for...working-12649/ for testing the sensor. I also read a few threads where someone resoldered the board on the sensor or found a loose wire on the plug by wiggling and fixed it like that. After trying these steps, I think the end of the road for now is to ground it out per these instructions from this thread 91 Accord brake lamp dash light problem
Effective brake light warning fix.
So this solution may not address the root problem that some are experiencing but it's virtually guaranteed to make that brake light warning go away. I was getting the same issue while using LED upgrades.
Apparently not enough current is going through the circuit to throw the relays in the sensor units. It's a cool design if you check out the electrical schematics in a Chiltons or Haynes manual. Anyway, what needs to happen here is the white with green stripe wire needs to be drained to ground.
That wire is actually putting out ~10-11v positive at 0.004 amps. That means 40mW which is less than a thousandth of what the low-beams are consuming or about the same as a very dim LED that you'd see in a toy. You get the idea. It won't spark or get hot. It seemed strange but this is what the brake light sensor relays set out to do when they're working properly with standard working bulbs in place - it provides a ground to that wire.
The fix is super simple. Look for the neat bundle of wires in the black plastic tube in the trunk on the driver's side where you pull back the carpet liner (it can be kind of a pain because the carpet isn't that flexible and you have to clear the trunk hinges.) I carefully freed the wires from the split tubing and connected the white with green stripe "signal" wire to one of the two thick black ground wires and that was it. Just take the key out and put it back in again and turn to position II or start and you'll see the light went away (because the circuit in the instrument panel thinks that the brake light sensor is working and reporting normal operation.)
If you want to minimize cutting and splicing wires, you can be slick and just feed the exposed end of the green with white stripe wire into either the nearby power antenna harness (you'd have to make sure that you put it in the hole for the black ground wire) or the harness closer to the tail light where the trailer wiring is depending on where you pulled and snipped things. You could double over the length of bare copper or twist it up good so that it fits snug and won't fall out.
No having to tape over it, ignore it, deal with it, or go through the hassle of taking the shifter, console, trim, and cluster out to pull the warning bulb. Problem solved.
I don't know if should make a new thread on this- please feel free to move it if it should be. The problem I have is I can't clearly locate the white with green stripe wire and I do not want to cut the wrong one. The one circled in black looks more like green with white stripe to me than white with green. But it is the only one with a stripe green and white colors. The other one circled in purple is white with small green dashes on it (or maybe they are gray?). It is the only other white wire. Once I know the right one, I will just cut it and cut either of the two black wires? Then splice and tape?
There is also some kind plug back there plugged into nothing seen below. Just wondering what that is for.
Thanks again for your help. It is very much appreciated.
The white wire in the purple circle looks like the one you want.Just so you know, wire colors are called out starting with the main color, followed by a stripe (might be little boxes too) color.
As for the plug in the trunk, it's not for your model (probably for a wagon), so it's not used.
Last edited by The Toecutter; Sep 15, 2019 at 04:27 PM.
Thank you for responding. Could that plug be used to ground the wire? I cut the one circled in purple. I attempted to ground it to the black ground wire on the antenna. The antenna is not working as it has no mast and I had just cut the wires on it to test the motor. (It tested fine on a 9V battery.) Since the black ground was already cut, I attached the white with green stripe to it, but the Brake Lamp indicator light did not go out.
I don't know if something about the antenna would cause that and I should try cutting one from the bundle. I don't much like cutting wires in that bundle, so if it isn't going to work anyways I would rather not cut it. I was glad the instructions gave the antenna as an alternate place to ground. I just made a post specifically about grounding the wire https://www.hondaaccordforum.com/for...ght-off-67142/ to see if I can get this light out. As I am typing here, I am wondering if the wire could be loose or such further up hence grounding at that point isn't working? The wire bundle looks in very solid condition, undamaged, etc, so it doesn' seem likely. I don't know if I just didn't ground it somehow with that antenna. I don't know much about wires/grounding a wire, so trying to learn.
So the wire is just cut and sitting there while I wait to see if anyone could let me know if the ground on the antenna could be "bad"?
I don't know if a ground wire can be "bad."
If it can and it's worth trying to ground the white/green wire I already cut to the black wire in the bundle- I was wondering if I can just remove a section of the wire insulation with wire strippers instead of actually cutting it? Then wrap the white/green around and tape it with electrical tape. If anyone could send a few quick words on this would be greatly appreciated. I don't know what to do next.
Have a multi-meter? Set to resistance (ohms) and measure from that wire to a good solid metal part nearby. If it reads near zero then it's a good ground. Depending on your meter, it might be a couple ohms.
If it's not a good ground, it'll either show open-circuit or it'll be flaky, jumping around when you wiggle the wires.
So the red probe goes on the wire? And the black goes on a solid metal part like just the metal side of the car? Or I connect the wire to the metal side of the car? And place both probes on it? I'm sorry. I know nothing about this. Should I just cut the black ground wire in the bundle and attach it to that? Can I cut it inline and tape it?
And if it isn't grounded, does that mean the wire has a short somewhere else? I don't know why it wouldn't just ground it and the Brake Lamp indicator would go off. Can I just remove the plugs from the sensors? Also, can I just disconnect the bad antenna by the plug and just leave it in unplugged with no harm to any other electrical needs?
Thank you very much. I have been trying to google and search and I have not been able to find anything for the complete lack of knowledge I have on this.
So the red probe goes on the wire? And the black goes on a solid metal part like just the metal side of the car? Or I connect the wire to the metal side of the car? And place both probes on it? I'm sorry. I know nothing about this. Should I just cut the black ground wire in the bundle and attach it to that? Can I cut it inline and tape it?
And if it isn't grounded, does that mean the wire has a short somewhere else? I don't know why it wouldn't just ground it and the Brake Lamp indicator would go off. Can I just remove the plugs from the sensors? Also, can I just disconnect the bad antenna by the plug and just leave it in unplugged with no harm to any other electrical needs?
Thank you very much. I have been trying to google and search and I have not been able to find anything for the complete lack of knowledge I have on this.
In my other post, I asked about the rez cap sensor, since you were changing out the booster that maybe something happened to it. That might be a place to look as well for a problem.
When measuring resistance, it doesn't matter which meter-probe is which. One probe on the wire you're checking, and the other probe on a BARE metal part. A good ground for checking might be the mounting bolts for the antenna motor. Besides, a good ground like that is probably the best place to put that wire anyway.
I separated the discussion about the brake-lamp warning from the other thread because it seems like a different topic.
I understand that Jim, but if he pinched the wires while removing the booster, then they could be related. My thinking is it wouldn't hurt to look since we all know he was right in that area doing some other work. Just a thought.
Brake-Lamp warning light on 91 Accord
Effective brake light warning fix.
