Brake lights not working

[lordgorlok]

no brake lights

I had an issue with my brake lights on my 96 yukon slt. My brake lights and all turn signals wouldn't work occasionally. I found out that the chmsl (center high mount stop light), still worked, along with the running lights. When I tried the hazard lights, they didn't work either. But when I jiggled the flasher relay back and forth, it would click, and all the lights would work. I checked the brake switch, the turn signal stalk, and all fuses, and then finally bought a flasher relay from auto zone. Problem solved. It turns out that because the rear turn signal, hazard, and brake lights all use the same filament in the same bulb, all the power goes through the flasher relay. $12.99.

 

[DjWooPig]

so i just replaced my brake light switch, and still dont have any brake lights, however when i trigger my trailer brake switch, the brake lights work. Im thinking its the flasher relay. Where is it located? I have a relay spot for the brake lights under the hood, but it doesnt have contacts.

 

[SunlitComet]

dj when applying brake the flasher is not used and bypassed. it is important to find out where the trailer brake controller output is spliced into to so i can pinpoint here the break is at. in the meantime check both stop/hz and turn/b-u light fuses and activate and deactivate your hazards using the switch on the column and try the brakes again.

---------- Post added at 04:55 PM ---------- Previous post was at 04:54 PM ----------

also provide your vehicle year please.

 

[DjWooPig]

dj when applying brake the flasher is not used and bypassed. it is important to find out where the trailer brake controller output is spliced into to so i can pinpoint here the break is at. in the meantime check both stop/hz and turn/b-u light fuses and activate and deactivate your hazards using the switch on the column and try the brakes again.

---------- Post added at 04:55 PM ---------- Previous post was at 04:54 PM ----------

also provide your vehicle year please.

Sorry, vehicle is 1999 GMC Yukon 4WD
Pulled and checked fuses under the hood. Unless there is another fuse block somewhere all where good. Activated hazards on column with no luck. Also i now have no hazard signals as well. I have park lights, head lights, turn signals, and reverse. No hazards or stop. There is a spot for a stop light relay on under hood fuse block but as i said earlier there are no contacts for a relay. trailer wiring is no hack job as i did it myself with proper tools and fittings. Trailer brake is spliced underneath dash into the stoplight (white) wire. Also noted that i am not getting any output current from brake pedal in my tekonsha menu settings.

 

[SunlitComet]

yeah open your driver door and you will find an access cover on the side of dash panel. you will find a mash of fuses in there labelled #1 stop/haz. that empty rely socket is provisioned on non-suv models.i think you just popped that fuse is all.

 

[DjWooPig]

wow im an idiot. Ive had this truck for 5 years and forgot that panel was even there. Will check in the morning. You are probably right.

 

[DjWooPig]

yep blown fuse. Might not have even needed to spend an hour with my big ass flopping around in the floor board replacing the BLS. Oh well its one less thing to worry about!

 

[tarh33l]

I have a 97 tahoe 4x4.
I curently have no "rear" "lower" break lights, or turn signals.
These are the only lights that do not work.

Front head lights, turn signals, running lights, and hazards all work.

Rear third break light, running lights, and reverse lights all work.

I have no rear hazards, turn signals, or break lights of course, because they are all the same light.

I have checked all fuses under the hood, and inside the vehicle, and they are all good.
The break light switch by the pedal seems to be working, since the third break light is still working, and makes the desired clicking noise. I could be wrong, but I am assuming this switch controls all three. The hazard switch, or relay seems to be working since the font hazards work. No clue at this point.

I am out of deductive reasoning to find the issue.

I have had this truck for a while, and I do all the maintenance on it, and have never had any light, or electrical issues. I am not sure where to start with this problem, and I dont have time, or money to buy parts, and test things with no positive findings. I need help with this issue, and any opinions or help is greatly appreciated!

 

[Kevin Jackson]

Same issue, trying out the fix today.

 

[Nicole Reyes]

My Brake lights do not seem to be working. All of the other rear lights work and the fuses all seem to be in good shape. Any thoughts on what to do next?

I'm