I have no brake lights on my 2000 Honda Civic EX. Its a two door five speed. I have checked the brake light switch and it has power in and out. Light bulbs are all good. All the grounds are good that I have been able to find. I have power to the PCM on the brake wire, but no power coming out. I spliced the wires thinking this would solve the problem and it didn’t. I am at the end of my rope. No blown fuses and the tail light and cruise works fine. I would appreciate any help.
On many vehicles which share the same bulb filament between the brake lights and the turn signals, the brake light wiring goes through the turn signal switch. An open in the turn signal switch can cause you to have no brake lights, although the high mount brake light will still work. If this is your situation, I would suspect a problem with the turn signal switch. This was a very common problem with midsize mid-'90s GM cars. Have you checked your high mount brake light?
Actually this system of brake lights is fairly simple. You have the 15 amp fuse to provide power to switch on wht/grn wire. And grn/wht wire all the way to the back to the brake lights. That grn/wht wire goes to all the brake lights. First thing I would check is the trunk for damaged wires. According to the diagram, there is three connectors and a splice between switch and lights.
The high mount brake light doesn’t work either. The turn signals work. Both appear to be on seperate circuits according to the wiring diagrams that I have.
Why does the grn/wht wire go into the pcm, it has power when brake pedal is depressed, the grn/wht wire coming out doesn’t have power when the pedal is depressed. I have found no damaged wires in the trunk and all the grounds are securly attached.