The brake lamp indicator is on. This is the light that is on the bottom of the car symbol tht shows your doors and trunk open. It is NOT the brake warning light for low fluid and emergency brake. The reason it is on it because the 3rd brake light is not working. The bulb appears to be good but there is no power to the socket. All the other brake lights work including the spoiler. I've read that this is probably the right tail light sensor. I've got a Haynes manual but the electrical wiring does not appear to match my sensor plug. It shows the green-white wire from the 3rd brake light socket connecting to a green-blue wire on the sensor. The problem is that there is no pin on the circuit board where the green-blue wire connects. So can anyone advise on how to trouble shoot this to be sure it is the sensor? I've taken the sensor out and looked at the circuit board and it looks good. Is there a way to check this board?

 

You may have power to the bulb's socket, but is the ground intact? What condition are the contacts, corroded?

 

I checked with a trouble light by grounding it's lead on the trunk latch and putting the point through the green-white wire going to the socket and nothing. To make sure the trunk latch was a good ground, I then checked the pins on the sensosre plug and those light the light. I then used the socket for my ground and tested the sensor plug and it light up again so I'm pretty sure the ground going to the 3rd brake socket is good and the problem is no +12V. Contacts look good.

UPDATE: After messing with this this morning for several hours, I don't understand how this worked in the first place. I took rear deck carpet loose and saw that the 3rd light socket pigtail was had a connector on it. The Green-White wire from the socket + connected to a Green-Yellow/ Brown wire going running to the right tail light plug. There, it connected to a Green-Blue wire on the sensor plug. The sensor circuit board has not pin to mate to the connector for this wire. How did it ever get voltage? I'm pretty good with electronics so this is really frustrating. Can someone please shed some light on what is going on??

 

Update: I have not worked on this since Saturday (9/12). I just put everything back together and was going to try an replace the 3rd brake light bulb even though it appears good visually and when checked with an Ohm meter. So Sunday, the dash light ws still on. THen yesterday it was off but 3rd brake light still not working. Then today, the dash indicator was on again. I'm still not sure why but I'm going to replace the bulb and see. Don't think that will fix it though.

 

I have a tenth anniversary accord 1993 and have been having a slew of troubles. My transmission went out (or so I thought) so I had it replaced with a new one. Five months later, it is doing the same thing again. I believe it is electrical and not mechanical. Here is what is going on:

For the past few months, I have had a Brake Lamp indicator constantly lit on my dashboard. It is the warning lamp that is supposed to indicate that I have a bulb out. Only, there are no bulbs out. All work, both with my lights on and off. I viewed them in a reflection (store front) when I backed up to the window of auto parts store. All my parking lights work, when I press the brakes, they work too. I replaced them anyways and even put silicone bulb grease on them.

I went to the junkyard and brought some of the circuit boards that the rear tail lamps plug into (brown on drivers side and black on passenger side) and tried them. Still "Brake Lamp" indicatore lit on my dash! I tried to switch the bulbs with ones from the junk yard, and presto, the light went out on my dash board. The next day, it was back on!!!!!

Here's the wierd part. This is what makes me think the "brake lamp" indicator on my dashboard is related to my transmission. When my transmission goes out, the "D4" on my dashboard stays lit. I can take my car out of park without pressing my brake. If I don't press my brake, my tail lights don't light up. If I do press my brake, my tail lights do light up. There is a little solenoid that, when in park, if I press my brake, it is supposed to suck in, thereby releasing the shift lock. When my "D4" stays lit, the solenoid is stuck in and the shift lock is defeated.

Here's the thing about that: When this happens, I have two more solenoids from working cars, and they work the same way. So I am 99.5% sure it isn't a defective solenoid.

Also, this seems to happen only when the car has been sitting for a while, like overnight or while I'm at work.

I'll get in the car after it has been sitting, and turn the key. Sometimes, if I push the brake when turning the key, the brake lamp indicator will go off, sometimes it will stay lit.

So when the car is having this trouble, I push the brake and hear clicking under the dash board, from somewhere over the fuse box. When I release the brake, the click shuts off. One click on, one click off. Not really constant clicking, but only one when I press the brake, and one when I release the brake.

When my "D4" light is lit, my car is very sluggish, like it is stuck in 3rd gear. There is definitely no shifting going on when I drive. I can manually put it into 1st, but that is the only forward gear that is different than D4, D3, D2. I use it if I have to start from a stop when going up an incline, if my car is not working with this issue.

But this seems to clear istself up after about 15 minutes. I thought it took fifteen minutes of drive time, but discovered today, while trying to isolate this problem, that Just having the key in the on position, with the car not running, has the same effect. My car works fine after about fifteen minutes of current going through the circuits.

Once the "D4" problem shows itself, there is no clicking sound.

Is there a brake relay that can be pulled and swapped and where is it, what's it look like?

 

I'm still having the problem with the light coming on. It's intermittent though. All my taillights work. I have a spoiler on the trunk and the lights in it work also. The only light that does not is the 3rd light on the deck. I have traced the wires down that feed it and the one that supplies power per the wiring diagram goes to the circuit board on the passengers side taillight. The weird thing is, pin on the wiring harness does does not mate with a pin in the circuit board.
I'm not 100% sure that when 3rd deck light is supposed to work when you have a spoiler. I bought this car new in 1993 and I really can't remember if it ever worked or not.

 

I fixed my transmission problem by replacing the transmission computer with a rebuilt one. I bought it on ebay from a vendor based out of Ft Lauderdale, I believe. No more transmission problems whatsoever. Boy what a releif! To be able to drive without worrying about being stranded or Late to work. I think I spent $119 with a lifetime warranty. Turns out I didn't need a lifetime warranty anyways because I traded in my car and bought a brand new 2010 Honda CrV last July as a reward to myself for my new career as a nurse.
I am sure I could have driven my Accord for much longer if I so desired as it was working wonderfully. I know I got bent over at the dealership on the trade in, but I am okay with that. Hope this helps. Replace the transmission computer if you're having transmission troubles.

 

Anymore info? I also have the problem with my 10th anniversary also

 

Here's a good one for the Tranny TCU. http://www.cb7tuner.com/vbb/showthread.php?t=185004
As for the brake lamp, check for corrosion in the sockets and the sensor boxes. Most like the black box on the rear passenger's side. http://www.cb7tuner.com/vbb/showthread.php?t=136509

 

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.

 

Brake lamp goes on when I drove my 94 Honda Accord over a big hole on the street. The bump and shock must have knocked something loose. Lights work fine though. Now brake lamps goes on and off intermittently. As long as the brake lights work, I don't consider this a problem.

 

Since you only have one post I hope you get this: Can you just jumper the GRN with WHT stripe wire to the thick BLK on the Trailer connector? Anybody!