brake switch issue?

[DJ4180]

Was informeinformed by a coworker on my way in last night that none of my brake lights work. I have tail lights. Reverse and turn signals. So I figured I would check the fuse. The fuse just inside the drivers door in the panel is fine. So I decided to check the relay I popped the cap under the hood and there is no relay where the diagram says the brake light relay should be. Wondering if this is normal. And why I don't have brake lights. Was thinking the switch next. But the no relay really messed with me. For the record it is a 99 tahoe 5.7

 

[MO Viet Vet]

Make sure you have power in to the brake light switch and power out when depress the pedal. Typically they stick on when bad but can be bad this way too. Bear in mind also that brake light signal goes thru the turn signal switch so that brake lights and turn signals can work at same time, so may be a problem there but the brake light switch sure would be less expensive.

 

[DJ4180]

Thanks. I'll have to have a look at it. Makes me wonder how long I've been driving like that

 

[MO Viet Vet]

I doubt there ever was a relay plugged in where you looked. They don't just jump out of there. To check you can remove another relay and plug it in and see what happens. Same amp rating relay by the way.

 

[lesterl]

Relay is only there on trucks......

Check white wire on turnsignal switch (brake switch power input to turn signal switch for passthru to the tail lights.)

If no power on white @ Turnsignal switch then possible bad brakelight/ TCC switch on brake pedal, or a bad 20A stop/haz fuse (do the hazards work?)

If power @ turnsignal switch, then you probably have a turnsignal switch bad if turn signals flash.....