I have a 1990 Honda Accord LX Sedan that I just purchased the other day. I just noticed yesterday that the BRAKE LAMP warning light was on. My wife was following, so I called her. She said that the left lamp works as normal, all the time... right lamp and 3rd lamp in the rear window do not light once the BRAKE LAMP warning light comes on. If I turn the car off and restart all is normal until the brake is pressed. Sometimes once, maybe 4-5 times before the warning comes back on. I checked all of the bulbs and they are correct and contacts are clean. I also looked under the steering wheel and the brake switch on the pedal assembly is definitely not 13 years old, so it has been replaced already. Any other areas to look?

Thank you!

 

Check the grounds

 

May be a problem with the right brake light failure sensor.

https://honda-tech.com/forums/honda-accord-1990-2002-2/cb7-brake-light-warning-circuit-3009319/

 

I had forgotten about posting in that thread. Glad it came back up. I tried junkyard sensors on both sides and that brake lamp indicator still comes on. The diodes are fine. The fault is somewhere else along the path from the diode to the dashboard. Possibly at the bulb itself on the dash. I do think the the problem is related to moisture or very moist air because although that light is on a lot, it's guaranteed to be on when it's raining. I just didn't have any more time to tear the dash, liners, etc. apart trying to find whatever little thing it is that has corroded and causes that dash indicator to light.

 

Thanks guys, I read through the lined thread before posting. Seems to me that the issue there is that the dash light stays on but all lights are actually working. My rear window mount and right tail will actually fail to light when pressing the brake but the left tail will work. Once the "failure" has occurred, then only the left tail will illuminate until the car is stopped, parked, and restarted. the 2 other rear brake lights may or may not come back on and return to working order. I may check that relay box in the right tail though. Its been so blasted cold here in MN that I have zero ambition to work on it at this point...

 

I included that link to show the brake light failure sensor. Actually, that sensor or the wiring right there can cause the problem you're describing and has been known to many times be the issue.

The left side, right side, and center mount brake lights all share the same ground at ground location G701; albeit on a few different wires attached to that same ground bolt. So, it is less likely to be a ground issue.

Power to feed the right side brake light and high mount brake light runs through the right brake light sensor.