Headlight Relays with Hidden Headlights

[thethee]

Well the hard part is over. Got it all pretty much done but have to wait until I refit the front clip to see the results. Managed to find a shop locally that supplied me with the proper connectors so there was no troubles with double connections.

I used 10 mm² wire from battery to breaker, 10 mm² wire from breaker to relays, and 4 mm² for the rest so should be all good. Didn't have much colours to choose from unfortunately.

Thanks for the help guys!

 

[tbm3fan]

Looks just like the one I built 5 years ago. Circuit breaker on other side instead.

 

[thethee]

Well the hard part is over. Got it all pretty much done but have to wait until I refit the front clip to see the results. Managed to find a shop locally that supplied me with the proper connectors so there was no troubles with double connections.

I used 10 mm² wire from battery to breaker, 10 mm² wire from breaker to relays, and 4 mm² for the rest so should be all good. Didn't have much colours to choose from unfortunately.

Thanks for the help guys!

View attachment 559631

Finally got around to finishing this and it seems to work great.

Quick question though @Big_John, right now with low beam there seems to be some back feed through the high beam bulbs. Is that something to adress or just a result from higher voltage through low beams?

 

[Big_John]

Finally got around to finishing this and it seems to work great.

Quick question though @Big_John, right now with low beam there seems to be some back feed through the high beam bulbs. Is that something to adress or just a result from higher voltage through low beams?

View attachment 565168

My guess is you have a bad ground.

 

[thethee]

My guess is you have a bad ground.

Thanks, will look into it.

 

[DocGonzo]

I converted my 69 T&C wagon to have the 300 hide away headlights. I didn't want to spend $300 on a stupid original relay so I made my own circuit for the headlight motor just using a fuse one relay and 2 general diodes for the low and high beams

 

[Big_John]

I converted my 69 T&C wagon to have the 300 hide away headlights. I didn't want to spend $300 on a stupid original relay so I made my own circuit for the headlight motor just using a fuse one relay and 2 general diodes for the low and high beams

That's a good solution if you don't have the existing wiring harness for the headlight doors. I wouldn't have bothered with the diodes and just pulled from the wiring to the headlight dimmer (floor) switch though. That would be the light green wire coming from the switch.

What I did (back on the first page) was add one relay to the existing wiring, using the existing circuit breaker etc. This replaces the expensive OEM relay, yet still preserves the original wiring and keeps the relay under the dash.

 

[Stoffauge]

Morning guys

@Big_John

I just did the conversion on my 71 Sport Fury and wired everything with you wiring Diagramm and used all new cables etc pp. Everything works but the low beam ! Have absolutely no clue why already followed all cables through and checked everything but I have no idea . Any idea what could cause the issue ? High beam works great and door motor also perfectly . Motor opens when turning on the low beams too but just no the low beams .

All lights got a new ground also with big cables.

Please help ! Took me some hours just to get it done very nice and now it’s not working :/

Regards , Fabian

 

[Stoffauge]

Nevermind got it going perfectly myself just didn’t really got it that the low beam relay needs ground too because it’s not drawn but makes totally sense .

Have a great weekend

 

[Big_John]

Nevermind got it going perfectly myself just didn’t really got it that the low beam relay needs ground too because it’s not drawn but makes totally sense .

Have a great weekend

View attachment 589644

LOL... I had started typing some things to try.

Guess I missed that ground point in my drawing. Electrical drawings are not one of my strong points and are usually just some rudimentary sketches on scrap paper. I tried to slick it up and missed the ground. Sorry for the confusion!

 

[Big_John]

Revised drawing showing GROUND for LOW BEAM RELAY

 

[thethee]

Finally got around to finishing this and it seems to work great.

Quick question though @Big_John, right now with low beam there seems to be some back feed through the high beam bulbs. Is that something to adress or just a result from higher voltage through low beams?

View attachment 565168

Boy has it been 7 months already? Got around to actually fixing this issue and turned out to be quite simple. Just needed to swap the wires for high beam and ground in the drivers left headlamp connector.

The low beam was using the high beam bulbs as the ground path. Oh well

 

[Gerald Morris]

Boy has it been 7 months already? Got around to actually fixing this issue and turned out to be quite simple. Just needed to swap the wires for high beam and ground in the drivers left headlamp connector.

The low beam was using the high beam bulbs as the ground path. Oh well

Yep! That **** CAN and DOES happen w car lighting, esp OLD ones. Right now, my right turn signal triggers BOTH front blinking lights. MAY be something w the hazard light flasher, OR one of the LED lights has shorted, again. (OR the turn signal switch has slipped a contact...)

Would be a greater worry if it was my LEFT front turn signal screwing up, but the right isn't such a much in traffic. The rear units work fine.

It's ALWAYS "simple" when one finds the actual problem, as these cars are simple. Be this as it is, the number of permutations and combinations when circuit elements fail, even in our old rods, exponentially increases with every additional element and junction.

 

[3175375]

Yep! That **** CAN and DOES happen w car lighting, esp OLD ones. Right now, my right turn signal triggers BOTH front blinking lights. MAY be something w the hazard light flasher, OR one of the LED lights has shorted, again. (OR the turn signal switch has slipped a contact...)

Would be a greater worry if it was my LEFT front turn signal screwing up, but the right isn't such a much in traffic. The rear units work fine.

It's ALWAYS "simple" when one finds the actual problem, as these cars are simple. Be this as it is, the number of permutations and combinations when circuit elements fail, even in our old rods, exponentially increases with every additional element and junction.

A lot of times, in my experience, the issue has been a poor ground.

 

[Gerald Morris]

A lot of times, in my experience, the issue has been a poor ground.

Often, but not always. I START w grounds. I have a bonding jumper from the battery, across the intake manifold, to the firewall, then down, under, to the back bumper, picking up the gas tank, and several sheet metal points in between.

 

[Oz Sport Fury]

I had a request a while back to do a thread on headlight relays. It's been done before on here, and I'm not doing anything different, although I am covering a relay for the headlight motors too.

You'll need two relays. As I always recommend, go with Tyco/Bosch relays. Don't scrimp and buy the Chinese knock-offs. I buy them from Amazon. Best deal I've found for genuine Tyco relays.

Amazon.com: Metra Install E-123 Bay Tyco Relay 12 Volt 30 Amp Each: Car Electronics

View attachment 131423


Next you'll need two sockets. These are available on Ebay or Amazon.

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Amazon.com: Absolute SRS105 5-Pin 12 VDC Relay Socket Interlocking Style: Electronics

A 30amp circuit breaker can come from any parts store.

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Some 12 gauge wire. To match the existing wires, you'll need black, red and purple. Some 8 gauge wire in your choice of color.

Some connectors as needed.
Universal GM Chrysler Ford Female Terminal Connector 14 12 AWG 25 Pack

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Two bags of Packard 56 connectors. These are the wider connectors for the headlights.

.3125 Wide Packard 10 12 AWG Female Lock Tab Terminal

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Here's how it's wired.

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This is so bloody awesome mate!!! I have a 71 Hideaway headlight complete front I bought for my 71 Coupe VIP III to install later on, I wasn't aware of these requiring a special relay setup open/close the covers.

 

[mgm1986]

This thread is super helpful and I have a question for those with more knowledge. I am planning to do almost exactly as @Big_John posted but I would like to install the relay for the headlight cover motor in the engine bay along with the relays that will be added for the headlights.

Is it acceptable to run all three relays (high beams, low beams, headlight cover motor) from the same 30amp circuit breaker?

Thanks for your input!

 

[Big_John]

This thread is super helpful and I have a question for those with more knowledge. I am planning to do almost exactly as @Big_John posted but I would like to install the relay for the headlight cover motor in the engine bay along with the relays that will be added for the headlights. Attached is a rudimentary drawing of my current plan.

Is it acceptable to run all three relays (high beams, low beams, headlight cover motor) from the same 30amp circuit breaker?

Thanks for your input!
View attachment 636879

I would use two circuit breakers. One for the lights and one for the doors.

The factory used a 5 amp breaker for the headlight doors.

I didn't do the math to say that the draw across the 30 amp breaker would be too much. Someone else can figure that out if they want... My thought is it might be better if the headlight circuit is by itself. Let's say you have an issue with the door motor or the doors and it's drawing a lot more current than it should. That trips the 30 amp breaker and now you don't have headlights. If the door motor did fail, the easy thing to do is disconnect the power to it and open by hand. Kind of a "no big deal" fix that you can do in a dark parking lot. But if that breaker is tripping and you don't know the cause, you'd have to figure out what's going on. So no scratching your head wondering if the breaker is tripping because of the motor or because of the lights.

BTW, I made a couple jumpers to carry in the car if so if a relay craps out, I can just jumper the headlight wires and still have lights... Again, thoughts are being able to do a simple repair in a dark lot or even on the road side and fixing it right when I got home. Headlights never break during the day!

 

[mgm1986]

Very good points, I will use two separate circuit breakers. I want it to be simple, reliable and easy to diagnose. Thanks for the input!

 

[tbm3fan]

I have now done away with those 30 amp circuit breakers and moved onto blade fuses in a small box. Seen here is the one in my Cougar which supplies low beams, high beams, ignition, and electric choke. A great theft deterrent also. I just remove the good 15 amp blade fuse and insert a bad one. How many people on this planet will figure that one out on the fly?