kevint1030

Hi, I'm completely stumped trying to figure out what is wrong with my brake lights for my '05 Civic EX coupe. My brake lights won't light when I hit the brakes, but the OEM spoiler LED brake lights work. I've checked fuse #7 (brake/horn) and it looks good and swapped it with the spare 15 fuse in the under hood fuse box. I replaced both bulbs with new Sylvania dual element bulbs #7443. My hazards and turn signals work, which use the same bulb. Upper tail lights and reverse light work. My cruise control did stop working about a month ago so I checked the connections under the steering column thinking something came loose. Still no luck. Any one have any ideas or experience with this issue?

lazlong

The cruise control won't work if any of the brake lights aren't working, it's a safety feature.

With both of them not working suspect it's either the ground or the switch on the steering column. Put a weight on the brake pedal to actuate the lights then check for voltage at the connectors or sockets. If you have voltage then it's the ground. If no voltage I suspect it's the switch.

kevint1030

Would the switch have different contacts for the spoiler brake light? I'll check the ground. Thanks for the tips!

NDNV

Check your brake pedal position switch for failure.

kevint1030

So I've looked at the brake switch. The "plunger button"..idk what to call it lol.. is not jammed. When I disconnect the switch my spoiler brake light stops working. Should mean the switch is functional right? I'm going to dig for my multimeter out of storage, but I was thinking about the grounding issue. Each side is fed with one main wire which branches to the three bulbs. I suspect the ground would be before the split, so if it's a bad ground the entire rear light assembly shouldn't be working.