Hello,

I'm not great with cars but I am good with electrical stuff. I seem to be struggling with a weird brake light issue on my 2005 Honda Accord LX.

Stupid question first but these are the brake lights in red, correct (not my car)?
http://carphotos.cardomain.com/ride_...4019_large.jpg

It appears my 3rd center brake light works correctly but the two side ones don't. They are always off when the headlights are off and always on when the headlights are on, pressing the brake does nothing. All the other lights work fine.

I checked the fuses and then checked the brake switch, it appears to be working correctly but I could be wrong. There are four wires red, white/black, green, and brown. The red and white/black short together when the brake is pressed, the green and brown are short when the brake is not pressed, but open when the brake is pressed. Is this how the switch is supposed to behave?

Is there another explanation for my brake light problem?

Thanks!

 

Yes the switch testing is correct.

Please check the bulbs - they are dual element. One could be burned out.

Next, check for voltage on the WHT/BLK wire of the bulb socket when the brake pedal is pressed.

 

It's strange and surprising, but I could not find a circuit diagram for brake lights in my 2003-2007 Accord Shop Manual. Describes replacing LED's and checking brake pedal switch, but no wiring diagram! It's a large manual and may be there but out-of-place, but I dont' think so.

Problem suggests perhaps a ground path problem. Suggests checking grounds in the trunk carefully.

good luck

 

In the service manual, it should be under Body Electrical, Exterior Lights, Circuit Diagram, Circuit Diagram - Brake Lights. Page 22-184.

 

Thanks RB, I paged over somehow.

regard

 

After viewing wiring diagrams and reviewing your post, the problem suggests a wiring damage, perhaps from someone wiring trailer lights. Do you have a bumper hitch?

In any case, you will need to investigate the wires in the trunk to locate damage/cross-connection.

good luck