Brake Light and Blinker Help

[Killer Frogs]

Brake lights are not working. I have a 73, but it was built in October of 72, so I've been using that wiring diagram.

I started doing some hunting around with the test light. In the process I found that when the left blinker was on, the power on the after market radio would go off, then the radio would come back on.

A little more hunting eventually led to the blinker relay frying, I had just put a new one in. So now no blinkers ?:?

Blinkers work out back. When I press on the brake pedal the red and black wire on the emergency flasher switch lights up (with a test light) when I hit the pedal. So my pedal switch is working. I'm thinking there is a problem with the wires coming from the turn signal switch.

I'll rewire the radio in case this is the source of the drain. Not sure if I have multiple problems or just one with the radio.

 

[frankolive]

Check your grounds. If a circuit can't ground it can do some strange things.

 

[doghows72]

^^^^^ Agree check all those grounds. Each turn signal and brake light housing has its own and if one is bad it will ruin your day.

 

[Viperwolf1]

Brake lights are not working. I have a 73, but it was built in October of 72, so I've been using that wiring diagram.

I started doing some hunting around with the test light. In the process I found that when the left blinker was on, the power on the after market radio would go off, then the radio would come back on.

A little more hunting eventually led to the blinker relay frying, I had just put a new one in. So now no blinkers ?:?

Blinkers work out back. When I press on the brake pedal the red and black wire on the emergency flasher switch lights up (with a test light) when I hit the pedal. So my pedal switch is working. I'm thinking there is a problem with the wires coming from the turn signal switch.

I'll rewire the radio in case this is the source of the drain. Not sure if I have multiple problems or just one with the radio.

A lot of contradictory statements in here. I can't tell what works and what doesn't. There are 6 bulbs that need to be looked at when troubleshooting the turn signals or hazards; 2 front turn, 2 rear turn/brake, and 2 turn indicators. You need to list how these work during the different turn switch and hazard switch positions.

Hazard flasher has red-white and white-red wires. Brake switch has red-black.

 

[Steve83]

I have a 73, but it was built in October of 72, so I've been using that wiring diagram.

Use the '73 diagrams:

...when the left blinker was on, the power on the after market radio would go off, then the radio would come back on.

When? When you turned the blinker off? Or after some period of time with the blinker still on? Was the blinker blinking while the radio was off?

A little more hunting eventually led to the blinker relay frying...

What does that mean, exactly? You damaged something while hunting for this problem? Or your hunting resulted in you finding something that was already damaged? There is no relay for the blinkers, and "frying" is vague slang. If you want specific help, you have to use specific terms. We can only see what you type, so choose your words carefully.

...no blinkers
Blinkers work out back.

That's one of the things VW is talking about: if there are "no blinkers", then none of them work. If the rear blinkers work, then "no blinkers" is not an accurate description of what you're seeing. GIGO - if you confuse us, you're going to get confusing replies.

I'm thinking there is a problem with the wires coming from the turn signal switch.

What exactly makes you think that? Can you see damage on them?

...the source of the drain.

What drain? I thought you were talking about lights and radio.

...just one with the radio.

If you think you only have a radio problem, why didn't you put "radio" in the title of this thread?

 

[Killer Frogs]

Ok, I' simplify things. Sorry to be confusing, probably to much info.

What is not working as far as lights go:
-no rear brake lights
-no hazards on rear
Not a bad bulb, I did test the sockets with a test light, and they are not hot
Everything else works on all lights; front blinkers and hazards, all tail lights and blinkers.

I know the brake wire is black and red an goes into the hazard switch. When I press the brake pedal the test light is hot. So I know my brake light switch is working.

Question Am I correct that the brake light hot signal is carried through the green and yellow/black wire?

So if this is true, there must be somewhere that the brake light signal does not go to the front blinkers. Is this in the turn signal switch? This is the schematics I'm using. http://www.supermotors.net/registry/media/874223_1

Thank you for your help.

 

[Viperwolf1]

Ok, I' simplify things. Sorry to be confusing, probably to much info.

What is not working as far as lights go:
-no rear brake lights
-no hazards on rear
Not a bad bulb, I did test the sockets with a test light, and they are not hot
Everything else works on all lights; front blinkers and hazards, all tail lights and blinkers.

I know the brake wire is black and red an goes into the hazard switch. When I press the brake pedal the test light is hot. So I know my brake light switch is working.

Question Am I correct that the brake light hot signal is carried through the green and yellow/black wire?

So if this is true, there must be somewhere that the brake light signal does not go to the front blinkers. Is this in the turn signal switch? This is the schematics I'm using. http://www.supermotors.net/registry/media/874223_1

Thank you for your help.

Yes, brake current (and rear turn signal current) travels through the green and yellow-black wires. The turn signal switch directs the brake current to the green and yellow-black wires only. It may go to one or both depending on the switch position but it does not go to the front lights, ever.

A key clue here is the hazard switch operation. It bypasses the turn signal switch and all column wiring completely. That leaves only two possibilities, 1) brake current is not getting to the hazard switch on the red-black wire, or 2) the green and yellow-black wires are broken somewhere between the hazard switch and the rear lights.

When testing the brake switch you should have 12V to one side at all times. The other side should have 12V when the brake is pressed.

 

[Killer Frogs]

I discovered I don't have any power on the yellow/black and green wires under the hood. I can't tell where these wires go once inside the cab.

Also, what are the orange, purple, and black/red wires in this picture?

Thank you.

 

[Viperwolf1]

I discovered I don't have any power on the yellow/black and green wires under the hood. I can't tell where these wires go once inside the cab.

Also, what are the orange, purple, and black/red wires in this picture?

Thank you.

The turn wires go to the hazard switch then the turn signal switch.

Orange-main fuel sender
purple-brake warning switch
black-red--backup lights

 

[EricLar80]

Make sure you check your blinker fluid:
http://kalecoauto.com/index.php?main_page=product_info&products_id=22

 

[Killer Frogs]

Thanks EricLar80 %) plenty of blinker fluid!

I'm making progress, I now have rear blinkers! But I'm not sure what I did, must have been a short that I reconnected. But still no brake lights and no hazards out back. Coming out of the turn signal switch everything works, at the connector in the picture.

I'm wondering if I have a bad hazard switch? The blue/white and green/white flash when the hazards are on. The black/red wire lights up (test light) when pedal is pressed along with the white/red wire. Where can I test the current that should go to the lights? Trying to work out to find the problem.

Thanks

 

[Viperwolf1]

White-blue is right front turn and indicator. Green-white is left front turn and indicator. It makes sense that you see voltage there.

Instead of measuring current just unplug the hazard switch. It's just hooked up in parallel with the turn switch so everything else should work normally without it. You shouldn't see voltage on the white-red wire if the haz switch is off. You can also unplug the turn signal switch and put the haz switch back in the circuit to test the hazards only. It looks like you have a problem with the brake circuit and most likely it's in the turn signal switch.