Headlight Relays

[namba209 (R.I.P.)]

Jeff, how about the number and color of the wires at the contacts, plus the operation or name of what each contact does. This is a simple diagram of what I used on Willit? for all the peripherals so I don't use the ignition switch to power everything. The colors are what the wires were on the "Bosch" type relays i got. HTH.

[markandson]

Well, I prefer to use the word Coil rather than trigger and common instead of 12V in, but that's just me being too technical.

[simplemind7]

this is the numbering system of the kind of relays i use at work, don't know where we get them, but they're what i'm used to.

85 and 86 are the coil that operates the relay, 30 is the common connection of 87a and 87, 87a is normally closed, and 87 is normally open

[namba209 (R.I.P.)]

It's just semantical terms that were in the pamphlet I got with the relays. But they work just as you've both stated. A small current at 12V operates the coil which actuates the switch inside the relay and allows the high current into contact 30 and out through contact 87. With the coil inoperative, or no flow through the coil, the high current available at 30 will flow through contact 87a. HTH.

[fsrowsell]

Thanks for the helps guys.. just on more quick one... In Brendan's drawing he has the two relays connected from 30 to 87(NO), but Jeff in his drawing on post number 8 shows his relays connected from 30 to 87a(NC). which is correct? Thanks

[simplemind7]

normally open means the lights are normally off, and the switch would activate them

normally closed means the lights are normally on, and the switch would deactivate them

so i think normally open would have the lights on when they are up, and normally closed would have them on when they are down... if you are using the microswitches. if your using a toggle switch inside the car then i guess it doesn't really matter, if you hook the relay up backwards, then just mount the switch upside down

[fsrowsell]

Thanks Brendan, this is what have put together from all the info that I gather here on this thread.... I well also be hooking up an on/off switch for the head lights.... Thanks Felix

[nobody]

This is just an idea, instead of mounting an on off switch somewhere why not put some type of microswitch around the front cable area to turn them on and off? Easy to get to and retains some of the original function and wiring.

[simplemind7]

the way that circuit will work is that when the on/off switch you added is off, the lights will operate as they normally would, when they are up, they turn on, when they are down, they turn off. when your on/ff switch is turned on, they will turn on regardless of what position they are in.

is that what you were trying to do? or did you want it so you can turn it off if they are up? in that case, run the on/off switch in the wire between the microswitch and the relay.

[fsrowsell]

Brendan, I would like to be able to turn the headlights on/off while they are up... So your saying in order for me to that all I need is to install an on/off switch on the yellow/black wire between the microswitch and my relay. and I do not need to run power to that switch... This all good assuming that the microswitch is working correctly. Felix

[simplemind7]

yes, thats what you need to do. i think thats what one of the the PO has done to my GT since there is a switch under my dash that is not in the wiring diagrams and has 2 yellow wires going to the headlight relays, guess i have to wait until i have the lights in there to see.

[fsrowsell]

Pleasee see attahed word doc... Thanks Felix

[simplemind7]

if everything you put in that document is correct, then relay #2 is bad because if terminal 30 has power, either 87a or 87 MUST have power.

also, the microswitch is not triggering relay #1 properly, i assumed that the microswitch sent voltage out, but it could be a negative trigger. actually, if it were a negative trigger, it would have caused a dead short when you turned on the on/off switch, this leads me to believe that the microswitch isn't working properly or the wire from it isn't getting to the relay. i would suggest taking this wire off the relay and using a multi meter to test what is happening at it when the lights are up and down, the post the results of that test.

oh, and one more thing, it says that you have power running directly from the battery... once its working, it will be possible to leave the lights on when the car is off... i guess its just a matter of preferance, but i would rather have the lights turn themselves off when i turn the car off, this would be done by running what is now the battery wire to the ignition. and it says "this has power coming from the battery + side" it sounds like its just a wire from the battery terminal, if that is the case, make sure it has a fuse.

[fsrowsell]

OK, this morning I ran some test and came to the conclusion the I am nor receiving any power from my hi beam switch on the steering wheel (green wire) that goes to the 86 terminal on relay #2. What I did to prove this was I crossed 30 with 86 on relay #2 and the lights came on. How do I fix this problem? Thanks Felix

[simplemind7]

i'm not really sure how the high/low beam switch works, i assumed that it was normally no voltage going through it, then when it was switched to high beam it would get voltage... someone else will have to fill in exactly how its supposed to work.

one thing i'm still puzzled about is how neither the low or high beams comes on when terminal 30 has voltage, since there will either be a connection from 30 to 87a or 87 at all times. try this, reverse the high beam and low beamwires on terminals 87a and 87, if the lights come on, then your wiring is bad, if the lights stay off, then your relay is bad.

[gr_diver]

In my 78 Ascona, when you turn the rotary main headlight switch to the II position (low/high beam), ONLY ONE CABLE GETS POWER. This cable goes to the steering coloumn switch, which during operation routes voltage to either the low OR high beam cabling. The only moment that both have power is when you use the signal position of the steering switch with the low-beam on. Now I assume that there might be some differences with the GT, as I see a microswitch that I am unaware of it's function.


When I did the relay mod a month ago, I initially used a circuit I found that uses old low beam cable to turn on the first relay, which acts as an on/off and feeds the second relay with power, and then the old high beam cable to control the second relay for output 87A for low and 87 for high beam. This setup would not work, because when I selected high beam, the healights would go completely off, as there was no voltage then at the low beam cable to keep the first relay on. In addition this setup would disable the signal function when the low beam is off.
So I rewired the relays, like in the schematic below. The first relay only controls low beam, and the second only controls high beam. Has worked like a champ!

HTH

[fsrowsell]

HTH, thanks for your reply for help... I'm at a wits in with these headlights... This morning I tried your schematic and headlights came on when I turn the key on..... BUT, when I clicked on the L/H beam switch the lights went out and only would come on again by me turning the key off and then back on. At least I'm getting closer then before. I rechecked all the connection to make sure they were just like your schematic. Also when I pull in on the L/H beam switch my white light on the dash would get brighter and when I hold the handle in. it also stays on, but dim when the lights are on after pull in on the switch. Any ideas? Bad ground some where or somethings like that.... Thanks Felix

[gr_diver]

I confess that I have not followed the thread from the beginning. You are mentioning the key, affecting headlights. Why is this happening? Are you running lights from switched source? So that they go out when you kill the engine? Or are they day running lights?

Are you sure you have independent +12 source to both relays? I mean, not feed the hi-beam relay through 87 or 87a of the low beam relay? Cause what you describe reminds me of the occasion I described in my earlier post, that switching to hi killed the whole system. In addition, what I have marked as "old" connection in the schematic, are actually the cables going to the headlights, just before the factory splice at the front end... And then the "new" are connected just before the factory splice that the "olds" were going to... DON'T PAY ATTENTION TO THE COLOURS I USED, THEY WERE RANDOM AS I DON'T KNOW GT WIRING.

In addition I am aware of a headlight relay and microswitches in some GTs, but I am anaware of their function (I have an Ascona). But if you do the mod right before the healights as I described, you will have completely unaffected switch circuitry, plus all the advantages of relays... Has any Previous Owner modified any electrics in the vehicle? Or are the microswitches and stock relay setup working properly? You should start from there...

Try this, with low beam on, gently pull the level to operate the "signal" function, before is engages the steady hi beam. This way the low should not turn off, and the hi would light for as long as you keep the lever there...

By the was, HTH means Hope This Helps, the name is Antony!!!! I'm glad I even took you a step closer.

[fsrowsell]

Thanks to everyones help and input I HAVE MY HEADLIGHTS WORKING!!! I am so happy to be able to drive around town again and not have to rush home before dark.... '
Anthony, like I said earlier I rewired it your way earlier and I had the problem Of the lights going out when I hit my hight beams. (By the way the GT's Head lights only come on when the key is on). I narrowed it down that is must be a problem with the microswitch. So, I found Gotrdan's(Classicopels) method of by pass the microcwitch and hooking the head lights up to the running lights switch. So now with the headlights up, I can turn them off and on by using the running lights switch. Thanks again everyone. Happy motoring Felix

[gr_diver]

Glad I could help!!!

Happy night driving!!!!