Headlights and brake lights don't work looking for guidence Options

[mb911]

Hi all. The 5 year project is wrapping up. I am working on making it street legal.

Here is what I have

74 chassis harness

914-6 column. Remove the head light relay from the 4cyl. Previous to that the headlights would not turn on anyway. If I jumper the yellow wire on the fuse panel #3 position then the low beam stays on. This is regardless of using the 914-6 column or not. The fogs work, running lights work , turn signals work. Brake lights dont but there were cut wires on the harness down by the switch so that is likely part of the problem.

I am also wanting to put relays on each headlight up front like 911s do to prevent any wire fire (IMG:style_emoticons/default/wink.gif) so my question is why the #3 buss wouldn't be energized without jumpering as shown in my picture.

My hopes are 2 fold. I am looking for a good high def picture of the brake light switch and wiring on a 74.

Then I am looking for the #3 buss(yellow wire low beam) issue.

Thoughts? Note in the picture I have the jumper hanging in mid air not attached.

[Root_Werks]

It almost sounds like you have a short, something is back feeding when you connect bus 3. Oh boy, electrical stuff can take time to track down. Triple check any non-connected wire isn't touching something.

[john77]

Not sure if this will be helpful, but if you scroll down on this thread Spoke posted a 74 foglight/headlight wiring diagram.

http://www.914world.com/bbs2/index.php?sho...=342181&hl=

There's a lot of good info about the headlight wiring in it.

[mb911]

It almost sounds like you have a short, something is back feeding when you connect bus 3. Oh boy, electrical stuff can take time to track down. Triple check any non-connected wire isn't touching something.

Not sure on a short but seems like the switch is a likely culpret.

[Chris914n6]

Headlights only turn on when the car is switched on.

[mb911]

Headlights only turn on when the car is switched on.

Yup know that so trying to track that down as well

[framos914]

Do your headlight assy come up but no lights?

You said the fogs are on but no low beam? fog light relay gets power from same place as your low beams (pin 56 on headlight switch) BR/BL wire goes to fog switch then to fog relay to turn on fog lights. From same pin 56 on headlight switch RD/WH wire goes to dimmer relay then YW wire from dimmer relay to fuse F4 and jumpered to fuse F3. Wires from fuses to headlights are good since you said low beams come on when you apply power to #3.

The problem has to be wiring from light switch to dimmer relay or dimmer relay to F4.

But if your fogs also only come on when you jumper #3 it's the light switch, wiring from ignition to light switch or ignition switch. Make sure you get power on pin 15 of light switch with ignition on.

[mb911]

Do your headlight assy come up but no lights?

You said the fogs are on but no low beam? fog light relay gets power from same place as your low beams (pin 56 on headlight switch) BR/BL wire goes to fog switch then to fog relay to turn on fog lights. From same pin 56 on headlight switch RD/WH wire goes to dimmer relay then YW wire from dimmer relay to fuse F4 and jumpered to fuse F3. Wires from fuses to headlights are good since you said low beams come on when you apply power to #3.

The problem has to be wiring from light switch to dimmer relay or dimmer relay to F4.

But if your fogs also only come on when you jumper #3 it's the light switch, wiring from ignition to light switch or ignition switch. Make sure you get power on pin 15 of light switch with ignition on.

That is very helpful thank you. The fogs come on no issue. The headlights pop up no issue. So now I have to figure out where the dimmer relay is.. that will be today's project when I have a few minutes.

[mb911]

Anyone know where the dimmer relay is?

[sb914]

I think the square one . Not positive although.

[ClayPerrine]

The dimmer relay is only used on 4 cylinder cars. If you do a conversion to a six column, you won't have a dimmer relay.

Clay

[mb911]

The dimmer relay is only used on 4 cylinder cars. If you do a conversion to a six column, you won't have a dimmer relay.

Clay

Ok thanks then thats what I cut out already per your direction last fall. Just cant figure out why no power at #3 buss and why no headlights.

[ClayPerrine]

The power should go to the turn signal switch in the column. then from there it should go to either the low or high beam feeds to the fuse block, depending on the position of the turn signal switch.

Clay

[mb911]

The power should go to the turn signal switch in the column. then from there it should go to either the low or high beam feeds to the fuse block, depending on the position of the turn signal switch.

Clay

I am working on determining if there is power to the red and white wire from the chassis to the red on the switch. I would assume if I have that then it should work. If I flash to pass the lights come on.

[mb911]

And it appears no 12v at the headlight switch red with white tracer and black with blue tracer #56.

[mb911]

So here is the progress.

I have power to the 914-6 stalk with the headlight switch on and the key on.. however no lights unless I pull back on the stalk.

Thoughts?

[framos914]

And it appears no 12v at the headlight switch red with white tracer and black with blue tracer #56.

How about pin 15 on light switch with key on.

Since you have the 6 column I saw this thread with diagram from Jeff Bowlsby for a 6 cyl. 26, 27 & 28. Are turn signal, ignition switch and light switch.

http://www.914world.com/bbs2/index.php?showtopic=298370

[mb911]

And it appears no 12v at the headlight switch red with white tracer and black with blue tracer #56.

How about pin 15 on light switch with key on.

Since you have the 6 column I saw this thread with diagram from Jeff Bowlsby for a 6 cyl. 26, 27 & 28. Are turn signal, ignition switch and light switch.

http://www.914world.com/bbs2/index.php?showtopic=298370

I actually have power now and have traced everything back to the turn signal stalk. The problem appears to be the contacts? Not sure yet as both switches I have do this.. very frustrating but I have eliminated the wiring, and switch.. so now it looks to be the turn signal switch.

[Root_Werks]

My hazard switch is sort of like that. If you pull it out, nothing unless you push in every so slightly. Just worn out I guess?

[mb911]

To wrap this up. The diagrams all pointed towards the red wire on the stalk being 12v positive but in reality the white and black should be. This maybe unique to the 2 switches I have but regardless the switch now functions.. now to get brake lights working.