3rd brake Light not working

[SerpentDrago]

First Post !

1990 Accord LX - Auto -191k

So the Brake lamp indicator is on , and the Middle / 3rd brake light does not light up when pressing brakes .

Things that do work

Left brake light
Right brake light

When lights on , Brakes go from dim to brightly lit when pressing brake pedal


Things i've looked at / done
No voltage at middle brake socket/plug ,
Off course changed the bulb

Checked the Brown box on drivers side taillight , board appears to be good (does not look rusty bad)

Same for Black box on Passengers Side.

Searched the forums for answers but can't find a post with just the middle light out


Thanks !

[SerpentDrago]

I have a multi-meter and ready to test whatever i can to trace this issue down

[SerpentDrago]

Swapped the harness for the tail lights , Drivers side > passenger side , Still nothing on 3rd brake light , ever other light works perfect , also after swap also tested directly no power going to the Green / Striped white wired on socket.


Also Probed a 12volt source at one of the sockets on rear , and had the ground to my multi-meter on socket ground @ middle brake light , and it is grounding fine

[SerpentDrago]

could someone tell me the lead that the 3rd brake lights power connects to , so i can trace it or rewire it ?

[92a6]

did your car originally have a spoiler on it with led brake light in it?

[Bad_dude]

Has it always been like this since you got the car or just recently? Check and push the wiring at the socket to see if it's loose. Also check condition there. Go the rear passenger's side of the brake house, outer housing, trace the brake wire color to the 3rd brake light. Test the voltage at the wire harness at the passenger's outer light housing. If there's voltage there then you have a broken wire in between the housing and your third brake light. If no voltage, then test the plugs harness for voltage and keep going back until you find voltage and that's where the break in the wiring is. The 3rd brake light is connected to the outer passengers brake like harness.
Good luck.

[oyajicool]

could someone tell me the lead that the 3rd brake lights power connects to , so i can trace it or rewire it ?

Third brake light=High level stop LT is getting power from #5 terminal on right brake LT sensor, in accordance with wiring diagram of Haynes manual. Wire color of that #5 terminal is GRN-BLU and is changing color to GRN-WHT in some place before getting into the third brake light.

The diagram is a bit confusing to me but I hope this will help you.

[SerpentDrago]

As far as i know , there was never a spoiler on the car .

And its been out since car purchase.

SO out of the connector of the sensor in the passengers side tail light ? there should be a GRN-BLue and this is what goes to the third brake light which is GRN-WHT once it gets to the socket?

[SerpentDrago]

so there is a #5 terminal that is gren blu , but its on the LEFT taillight sensor , t
there is not even a #5 terminal nor a gren blu one on the right side

the one on the left , is the same color wire that goes into the trunk left brake light

[10thAnnivCB7]

happened to me 6 months ago and it fixed itself ,, 3 days ago it stopped working again ,, i never found a problem

[oyajicool]

so there is a #5 terminal that is gren blu , but its on the LEFT taillight sensor , t
there is not even a #5 terminal nor a gren blu one on the right side

the one on the left , is the same color wire that goes into the trunk left brake light

Well, I don't know what to tell you. The information I posted is based on wiring diagram straight off of Haynes, which is from Mitchell.

Try these diagram below. These are for European models but they may work on your car....





These are much easier to read than Haynes' diagrams.

[oyajicool]

The following is from Haynes for your reference.

[SerpentDrago]

Thanks ! with this info i should be able to run 1 single power wire to the light ! ;0

[oyajicool]

Haynes may have left and right, flipped on the diagram.

Anyways, hope you can figure it out!!

[lucifer1]

Jumper pin 1 and 5 together at right taillight to bypass relay box. If the l 3rd brake light works, relay box is bad. If it doesn't work, then look for an open in the grn/wht wire from the relay box to light.