BRAKE lights always on!

[weatherm]

like the title says ALWAYS on.. no matter what even when the truck turned off... I put in a new brake booster and I don't remember fiddling with anything but now the tail lights are just on. I checked the fuse box and didn't see any blow fuses... after I installed the booster my blinkers kind of work (its a 72 fj) so they are supposed to alternate on and off .. they just go off... but its better than it was for sure. the little push piston for the brakes is in so all that works.

I'm sure its a ground issue.. I have a good ground to the frame and to the body... When I turn on my head lights the left one goes out...

Any idears??

 

[Poser]

Running lamp part of the bulb or brake lamp part of the bulb?


Unplug the brake light switch under the dash by the brake pedal and see what happens...

 

['74 UA FJ]

Brake pedal is not returning far enough to (de)actuate the brake light switch?

 

[weatherm]

I unplug it and the lights go out

brake level goes all the way and presses the brake light switch all the way in ... works like thats supposed to

 

[bsmith123]

lights

check the wiring to all the lights on the left front side where you were working and make sure you didnt plug the always hot horn wire into your lights

when you try the turn signals you say they just go out right?

is that with the key on or off? you should not have TS with the key off so the hazards may be do the clunk

make sure the hazard sw is off

can you reach the RW and GW wires at the connector to the brake light switch you could pull this off and see if it is the brakes---lights dim or bright should tell you though---bright for brakes

at the back combis you have a GO and G wire ---pull the plug and see which has pwr---go should be haz and turn and G should be brakes and tail I think ---that'll get you part of the way

you could unplug the flasher too and see if they go out

The flasher is bi-mettalic so it needs to see enough current draw to make it work --- if there is a fault, the flasher may not work with either a ground fault or power fault. That will prolly be okay once the always on light prob is fixed

 

[Poser]

I unplug it and the lights go out

So let me get this strait:


You unplug the brake switch and the rear lights go out?



After you unplug the brake lamp switch, pull the headlamp switch and see if you have running lamps in the rear.

brake level goes all the way and presses the brake light switch all the way in ... works like thats supposed to

This collection of text does not make sense to me.

 

[weatherm]

correct... I unplug the brake lights from under the dash (the light sensor piston thing the pedal presses on) those connections.. I unplug that connection and they go out.

I plug it back in and the lights are on... with the headlights or not. There is no dimming with the lights with any combination's you guys have suggested.. I hit the brakes and the lights don't change... just a constant light.

key on or off the lights are still on.


Steps that created this problem:
Installed new brake booster
Tested brake booster (cranked truck up)
*crap* my lights won't go off

I looked at the connections to everything last night twice and all look good.

On another note my blower now works

 

[bsevans]

The brake light switch is sticking and not returning far enough turn the brakes off. I had the same problem to the point that it melted both lenses. A new brake light switch corrected the issue. I tried to fix the switch but it was very suspect even after cleaning and applying a small amount of grease. Maybe you can fix yours.

 

[bsmith123]

other lights

so when you pull the plug are the flashers and everything else working?

 

[Poser]

After you unplug the brake lamp switch, pull the headlamp switch and see if you have running lamps in the rear.

Please post up an answer to this.

 

[Kuhndog]

Weatherm, I had the same problem on my 72 recently and it was caused by the small rubber bumper falling off of the brake pedal. It is the rubber stop that actuates the brake light switch. With it gone the 1/4" space was enough to not turn the brake light swith off. Small rubber button available from Toyota. Hope this helps! Ben

 

[weatherm]

Poser: with the headlights on and the brake harness unplugged I HAVE running lights(dim).. plug it back in and I have brake lights (bright)

Kuhndog: Well I'll look into that, I appreciate it. I sure didn't see any rubber anywhere up there today at lunch.

 

[kissmyaxle]

Rhett I dont know whats going on with your lights man, but glad to hear your rig is running better....Put the doors on there and now mine wont start....i think the damn aliens have anal probed yours and mine caught something from it.

 

[weatherm]

Ben.. maybe the doors are so super bad that your truck is going to have to grown into them to be able to function with the level of badness because you raised the level?

Mine will fly down the road now quiet as you can get ! I love the Fat Mat stuff I put down... Ammo cans get installed tomorrow for waterproof storage!

 

[Poser]

Poser: with the headlights on and the brake harness unplugged I HAVE running lights(dim).. plug it back in and I have brake lights (bright)

Thank you.


Now, since we have established that:


Have someone watch the rear lamps and press the switch in all the way by hand and have them tell you if the lamps go out.

 

[weatherm]

poser: running lights stay on

On another note when I pull the hazards the back left light goes out.. for what its worth.

 

[dargreg]

Grounds ,bad light bulb,corrosion on wire .you name it,after reading this the last couple of days,it sounds like you had your brake swith on after installing your new booster,in doing so youve distutbed a faulty wire or something trying to take it down.I think every body has pretty muck covered posible solutions,it will be the simplest thing.

 

[bsmith123]

t/sing lights

have a look at the brake switch up by the pedal can you actually see it moving in and out?

if you unplug it and the light goes out then the switch is made all the time so either a bad switch or adjustment

a cheap test light helps a lot for lighting but one of your marker lights will work just as well it is just a case of going around and testing for power where it should and shouldn't be and checking all the grounds and connections

 

[weatherm]

update: I checked under the truck for loose or bad connections... I didn't see any. I did unplug the blinker wire harness and the lights go out and does not work when the pedal is pressed...

Off to buy a test light

bsmith.. the switch goes in and out like it should.... just weird how it could go bad on the install of a brake booster...

off to harbor frieght

 

[dargreg]

Just a note Irecently had a 45 that had got a punture in the harness just in front of the rear wheels.Two of the wires (cant remember which ones) had corroded over time,giveing false indicator and running lights.I could not find it until i unwraped the tape from the rear forward..soldered them up all was good.It might be something to look at.