Rx-7Addict

iTrader: (2)

My brake lights don't come on at all!

However, my taillights work perfectly. I checked the fuse in the driver's footwell, and it is fine. Any ideas? Is there some sensor.

Also, the center light doesnt come on while hitting the brakes. Is there a sensor or something I can check out?

thanks
-scott

HAILERS

Brake pedal switch.

rotaryracer1

iTrader: (1)

it is probably your "brake light switch" it is on your brake pedal arm under the dash. mine went out twice. it is very easy to replace and it costs about $6 at your local parts place. good luck

DC350

mine just went out as well. When i put pressure on the pedal i do not hear a little "Click" anymore I guess i'll have to get another one.

You dont have to get it from mazda?
Just a parts store?

silverFC

i had the same problem but it was my main switch in the dash

Gibenstein

iTrader: (2)

Bump Im having this problem is there anything else anyone knows about this issue ?

Icemark

Either the brake light switch

or if it is a S4 it could be the brake circuit board in the CPU.

Test the switch, if it is fine, then replace the CPU or the circuit board (again only on S4 models). The brake light switch runs right to the brake lights on S5 models.

And I have both rebuilt CPUs and rebuilt brake light circuit boards for the CPU on my website.

Gibenstein

iTrader: (2)

Are the horn and brake lights interconnected Icemark b/c I saw this post and I was wondering what you meant by it .

https://www.rx7club.com/showthread.p...t=brake+lights

Cuz my horn doesnt work either...

Icemark

The Horn and Brake lights use the same fuse

Gibenstein

iTrader: (2)

Is it dumb luck my horn and brake lights dont work ? Cause the "Stop" fuse looks good..

wai

I had the same problem before,
I think you have to take out the cpu and resolder the brake part

Icemark

Please meter the fuse or replace it with a known good fuse. If the ATF style fuse cracks (which some times happens when they get old) you won't be able to see it's blown/no good.

Also do the parking lights and headlights work? You could also have a bad 60 amp fuse under the hood if they don't.

Or is the CPU plugged in?

Gibenstein

iTrader: (2)

All my lights work headlights , inside lights , park lights , reverse lights.... Its just the brake lights.

Icemark

sure sounds like the fuse then...

Gibenstein

iTrader: (2)

Ok I just changed all the fuses work now... I fixed my clock like that yay !! But anyways no go on the brake lights. All my lights work I checked the switch and I am getting a reading out of it.. But I am not however getting a reading out of the wires for some strang reason ... Anyone help ?

Gibenstein

iTrader: (2)

Bump does the CPU give signals to the wires on the brake light switch.

Icemark

On the S4 the wires feed from the fuse, to the brake light switch, to the CPU, to the lights.

So if you have a S4, the next step is to go to the CPUs bottom 4 pin plug and check if you are getting a brake switch signal there, and if so, if you are getting the output from the CPU to the lights.

HAILERS

Here is a jpg of the stop light circuit. Why not pull the CPU plug and put a meter on the WG wire and see if you have 12v when you step on the brake pedal??? YOu do? Then jumper the WG to the G wire and step on the brakes. Go stop lights??? BAd CPU. Icemark will fix it for you.

Gibenstein

iTrader: (2)

Will do it tommorow. I am thinking bad CPU relay b/c all of the other lights work perfectly so I will test it saturday when I am putting in my oil line. YAY !!

HAILERS

Lets say it turns out to be the CPU. I think you could extract the Green/White wire and the Green wires from the connector and join them together (your favorite method) and have brake lights like a normal car. The CPU run seems to be just for a indication that you have a brake lite out. Otherwise the car should work like a normal car. You'd have to put some insulation lile electrical tape around the two wires connectors for obvious reasons.

HardDrive

Well I dont know if its a good idea or not to hook it up that way, I dont see why not at this point. But that does work.
I just checked mine cause I was haveing the same problem, only my blinkers and my brake lights where the ones not working while everything else was fine.
Brake lights are the CPU, Blinkers however I am not sure but am thinking the contacts in the switch might be funcky cause after i hit my head on the streering wheel they work again.

harley71105

That happened to me on one of my 88's about three or four years back....down on the floor to the left of your left foot next to the firewall and fusebox is a "CPU" ...
now this is not the ECU or main computer but the CPU...
it is a black plastic box and contains the circuit for the brake lights and two other circuits....you have to replace the whole thing unless you know someone who can repair electronic circuits...a new one is $450 but I got mine from an online salvage place for $50 so I bought two of them....I would wager this is your problem too...I replaced bulbs, fuses, brake pedal switch....then found this out...good luck...dude...