Brake lights and hazard quit working

Good morning,

I attached a wiring diagram for you to view. Check the fuse for power to the switch.

https://www.2carpros.com/articles/how-to-check-wiring

Then check voltage at the switch itself. It is under the dash on the brake pedal.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Roy

For information on stop lamp circuit diagnosis, refer to Diagrams, Diagnostic Aids.

Caution: Refer to Battery Disconnect Caution in Service Precautions.

1. Disconnect the battery negative cable.
2. Disable the SIR. Refer to Disabling the SIR System.
3. Remove the pushrod retainer from the brake pedal pin. Use snap ring pliers.
4. Unsnap the stop lamp switch from the pushrod.
5. Disconnect the electrical connector from the stop lamp switch.

Installation Procedure


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1. Connect the electrical connector to the stop lamp switch.
2. Snap the stop lamp switch onto the pushrod.
3. Install a new pushrod retainer on the brake pedal pin. Use an 11 mm (7/16 inch) socket in order to push a new clip onto the pin.
4. Connect the negative battery cable.
5. Enable the SIR. Refer to Enabling the SIR System in Restraint Systems.

If my cab brake light works doesn't that mean my switch is good?

Correct. If it works, then the switch is good.

This means either the turn signal switch is bad or the wiring to the bulbs is an issue.

Roy

Assembly Procedure

Important: Be sure that the electrical contact of the turn signal and multifunction switch assembly (2) rests on the turn signal cancel cam assembly.

Notice: Refer to Fastener Notice in Service Precautions.


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1. Install the turn signal and multifunction switch assembly (2).
2. Install the 2 pan head tapping screws (1).
Tighten the screws to 7 Nm (62 inch lbs.).


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3. Slide the 2 connectors (2) of the turn signal and multifunction switch assembly into the bulk head connector (1).


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4. Pop the wire harness assembly (4) into the wire harness strap (5). Install the wire harness strap (2) into the steering column support assembly (1). Install the wire harness straps (3) onto the wire harness assembly (4).
5. Install the upper and lower shrouds. Refer to Steering Column Trim Covers - Assemble Off Vehicle (Column Shift).See: Steering Column > Removal and Replacement

my turn singles work fine, my hazard lights don't work?

That would be from the switch itself.

Replace the switch.

Roy

the brake light switch?

The turn signal switch.

Roy

Got my switch in replaced it it took care of my hazard light issue. Thank you for that. still no brake lights. i am not getting power to my brake relay or fuse box in the under the hood fuse box all other fuses work fine. i took out the brake light switch it did not look good, replaced it. it is getting power but still no power to my fuse box or relay. third brake light works?

Okay, I attached a diagram for you to view. Check for power out of the multifunction switch with the brake pedal depressed with a voltmeter.

Roy

i replaced it to fix my hazard light issue and the brake light issue was there before. i will do it.

Let me know if there is power on those wires with the pedal depressed.

Roy

i will thank you.

You are welcome.

Always glad to help.

Roy

this has a trailer brake on it under the dash. not a very good looking job. The wires in the back are hooked to nothing there taped off would this have anything to do with it ?

If they go to the rear brake lights, yes. Check the colors and match them to the diagram.

Roy

i have a yellow, light green, dark green, brown, blue, orange. orange and brown are hot.

Yellow and dark green are the ones going to the rear lights. Check the diagram I sent you to verify.

Roy

i see what your talking about. these wires go to the trailer plug so i don't know what to do with them.

Do a continuity check to the rear lights from those wires to be sure that they are the wires.

Roy

I tested at the new switch 2 yellow and 3 dark green to the switch 1yellow is hot with brake on or off. 1 dark green was hot with brake on or off.

With brake on only the brown is hot. My cab brake light and all lights tail, turn, hazard back up all work.

What about the white and orange wires going into the multifunction switch?

Roy

the orange is hot brake on or off. the 2 white are not hot brake on or off. still no power to my brake relay under the hood.

any other ideas?

Hello, I'm Danny.

I've attached an ABS brake wiring diagram below for you. You mentioned you got the lights working. Are you trying to get a trailer brake to work? Let us know and we'll figure this out. Hope this helps and thanks again for using 2CarPros. Happy Holidays.

my truck brakes have been my problem and still are my problem.

what are these drawings for? I have a 2000 k3500 454 4x4 automatic stander cab .This seems different.

Sorry for the delay, where is the connector from in your picture? Where does that white wire go?

Roy

The white wire is hanging from the original wiring harness. no sign of it connected to anywhere.

If you look at the original wire diagram I sent you in the beginning, the white wire is from the brake light switch. It feeds the turn signal switch as well as the brake relay.

Test that for voltage with the pedal depressed.

Roy

should it be hot with brake depressed?

Yes, it should. Look at the diagram I posted in the beginning and you will see that wire feeds off to several places.

Roy

I tested the white wire it's hot when depressed.

What does it connect to?

i am lame on these drawings. i know it's right in my face. but i'm struggling here.

It goes to A1 in the wire diagram I sent you for the multifunction switch.

It also goes to the underhood fuse block for power to the relay.

Roy

i see where it goes to the stop light switch and to the relay, i don't see what it connect to at the rear of the truck.

do i need to open the harness did it pull out of there?

It does not connect to the rear of the truck. If you see where it goes to the relay, look down further and it connects to the multifunction switch at terminal A1.

Roy

so it just hangs at the rear of the truck?