1970 Charger, Headlight relays result in some STRANGE stuff.

[Kern Dog]

In 2013 I gave in to the pleading of a friend. He insisted that I should install relays for the headlights to keep the car from burning up. He integrated some relays into the stock wiring that resulted in some screwy things. The lights came on but wouldn't go off. Turning the ignition key off didn't work. I hit the dimmer switch and they went off and the doors closed.

The friend was confused and so was I. My limited experience led me to just replace the harness and go back to a stock setup.

Everything worked fine and still does but I have wanted to install some brighter lights like Hella H4 and H1 types. They pull more power so I figured to try the relay idea again. THIS time I bought a harness that plugged into the stock wiring with no cutting. I installed it as directed but once I tested it, the headlights came on just by turning the key. The switch wasn't touched. Pressing the switch had zero effect. Shutting the car off, the lights stayed on. To get the lights to go off with the ignition off, I tried the switch. This did shut the lights but the doors stayed open.

I put it all back to stock and everything worked as it should.

I thought that the concealed headlight system may be adding another snag in the system that the harness manufacturer didn't think of. I sent him an email and he responded quickly. He thinks that the system is "ground hunting" due to poor connections. He surely knows a LOT more than I do but I have never heard of that term before.
Has anyone here dealt with this problem before?

[70sixpkrt]

The only thing I know is if your using a new harness to the headlight motor, the wires are criss crossed. You will have to cut the wires at the pig tail and reverse them. I had to do that.

[Kern Dog]

Thanks. The headlight harness was new in 2013 and works fine. This "sub harness" is also new and designed to be installed with no cutting, just a plug-and-play deal.

[Kern Dog]

There are 2 relays, one each for low beam and high beam. I tried swapping the relays from side to side. No change.
I moved the drivers side ground to a better spot and now the headlights DO go out when the car is shut off. but each time I turn the key, the headlights come on without touching the switch.
I added grounds to the unplugged stock low/high plugs. No change.
I tried some used relays I had in the shop. One side stayed on even without the key being turned so that one is obviously stuck open,
The headlight door relay is clean, the spades are clean and the mounting screw is tight.
To me, the relays are supposed to only transmit power when the headlight switch is pressed. This is acting like the headlights are coming on because they are directly tied to ign ON , completely independent of the switch.

[Kern Dog]

I am trying to understand all of this and am not assigning blame. I simply do not know what is wrong and almost every that step that I make results in one thing: The headlights and doors worked perfectly fine before and now they do not. WHY is the question. Figuring out why is not so simple.
I unplugged the headlight door wiring and the symptoms continue.
I unplug the low beam plugs, no change.
I unplug the high beam plugs, no change.
I tried different relays, no change.
When the sensible efforts produce no results, I try shit that makes no sense.
Ignition on, switch OFF, lights still on, trigger plug pulled out slightly...Yes, there is power to the low beam when the low beams are on and power to the high beam when the high beams are on. Pulling the plug shuts off the headlights as you would expect.

Something about this kit, no matter how well it was made, upset the system to where it won't work right. It has been consistent today though. Ignition on, headlights on. Ignition off, headlights off. The switch is dead with the ignition switch on but works fine with the ignition off.
What is it within the system that is disturbed by the relay kit?. I am okay with it being something in the car itself. I'm not looking to blame Crackedback. I may even pull this out to test it in my other Charger. That car has the same style wiring, concealed headlamps and everything. The lights and doors work on the car too.
I can try the kit on my Power wagon or 67 Dart.

[70 sublime]

Do the relays themselves need to be grounded ?

[Kern Dog]

The # 85 terminal does. The diagram they provide does show them to be grounded but now that I think of it, I'll need to look at the harness itself.

[Kern Dog]

I turned the key, the lights came on....then when I pulled the wire plug from the dimmer switch, they went out.
I tried it again and pulled the plug to the headlight switch....and the lights stayed ON.
Crazy!
I've been looking at the FSM wiring diagrams to get an idea of where the power comes from. The headlight switch feeds from the welded splice going to the ammeter and ignition switch. I don't have an ammeter anymore.
The headlight door relay looks like this:

[b5blue]

Break down functions, Head light switch A: off  B: dash/markers  C: B+ head lights, doors relay "up" feed to activate relay. Relay not energized feeds 12 to down wire.
So door relay is fed 12+ to motor by harness not switch, the headlight switch just activates the relay.
Dimmer is just a 2 position switch A or B no other function.
Things to know: Door motor is grounded by black wire to gear box so through chassis, gear is switch so up moves contact to ready to go down and down to ready to go up.
I assume this kit must use high and low (Dimmer A & B) to activate relays. These relays must be "fed" 12V+ from someplace to get power to feed new fancy headlight bulbs.
Relays have many types, all use control volts with some just on and off others A or B and then some even more complex functions.
Most modern relays have a tiny schematic on the box showing what connectors (Pins) do what. So one wire will be activate relay and it will need a ground to do so there is 2 wires for each relay to function. Another wire is considered a "Supply volts" going into the relay for the activate to deliver to the output wire. so
ground
energize
supply
output
Headlights are really just wired 2 or 4 bulbs position. Depending on hacks and mods, alt. used and where/how you feed "supply" anything can go wonky and we know nothing of what you bought but functions told here work as told. (Remember headlights are fed 12V+ but doors are fed ACC position.)

[Kern Dog]

I think that I fixed it.

I tried another relay from my other '70 Charger. The lights acted the same way.
I pulled each fuse one at a time looking to see if the lights went out. It made no difference. The thinking there was that maybe I had tied another accessory into the headlight circuit and that it was possibly "back-feeding" some small voltage enough to trigger the relays.
I wired in a Bosh 30 amp relay according to a diagram posted here on this forum.
I think it made the difference.
The key ON, no headlights until I press the switch. SCORE!

[AKcharger]

This is worth doing as well
http://www.dodgecharger.com/forum/index.php/topic,168.175.html

[Kern Dog]

Here is the schematic that I used to wire the replacement headlight door relay.

[matchek]

For clarification I would like to understand your thinking, you had a relay there, but then replaced it with another relay from your 70 Charger and it did the same thing right?  If I understand correctly, what was the amperage of these two relays?

And then you installed a 30 AMP relay from this diagram - how did you get this idea?   How did you arrive at 30 AMPs?  Was the 30 AMP a brand new relay? 

Glad you got it - sounds frustrating.

One thing I am learning with the old Charges is they don't like a lot of mixing and matching with other non-stock parts. 

[Kern Dog]

Apparently, both stock type relays worked fine to operate the headlights and doors in stock form but they leaked a small amount of voltage....just enough to trigger the aftermarket headlight relays to turn the lights on without using the dash headlight switch.
The modern cube shaped relay was just a commonly found, easily sourced Bosch 30 amp unit that I had on hand.
I got the diagram on how to wire it from a thread on this forum.

[matchek]

So I take it the old relays were also 30 AMP, it is just that the new 30 AMP did not leak?     Trying to understand if you changed the circuit or if you just changed a relay with a like-for-like new replacement.

By the way, I no longer get email notification replies and did not change my settings.  Anyone else have that problem?

[Kern Dog]

I don't know the amp rating of the stock relays.
The guy that made the relay harness said that out of approximately 50 harnesses for 1970 Chargers, he hadn't seen the problems that I was having. I only switched to the Bosch relay as a test to see if it made a difference.

[G70464]

To go a different route why not use LEDs with resistors to make sure the hidden headlight motor knows when the lights are on or off.
Lower voltage and miles brighter, no crazy relays that make it more complicated.
Did it 6 months ago.

[Nacho-RT74]

Damn! Once again posting the false information about the LED headlights upgrade affecting the hideaways system motor


THAT'S FALSE!

Hideaways system works even WITHOUT ANY headlight connected!

Check this... and specifically read reply #35 about that

https://www.forbbodiesonly.com/moparforum/threads/led-headlights.204196/page-2

( it seems "somebody" didn't read it )