Headlight Relays with Hidden Headlights

[cantflip]

Is it possible to put the wires I currently have feeding the switch into a new plastic piece? Rebuild the replacement connector with the existing wiring instead of splicing a pigtail? (I would totally still have them send a 2' pigtail though, that just seems like a smart idea)

Best is still getting the entire harness, as @Big_John said. Good luck getting someone striping one to remove it for you, or even getting a proper pigtail.

You could just use the shell, as you mentioned, but you will need to carefully inspect each terminal... that's where the heat came from, one of them is cooked... so you would still need to replace that one and the switch. Removing pins from the shell is a matter of patience and creativity. You are unlikely to find the proper tool, which may have never existed in real world anyway. Picks, paperclips, needles and improper use of existing terminal tools is the standard operating procedure for this job. Then you have a shell to find, a terminal to find and wire to inspect. A short pigtail would force you to this, but also that entire wire may need to be replaced if the entire circuit got hot (vs just the terminal). You really need to do an assessment once you're in there.

I'd get the harness or pigtail before starting.

 

[thethee]

This all worked the way it was supposed to... Headlights were a little brighter etc... Until I went to turn off the lights. I quickly discovered that the headlight doors didn't work right at all. I could h"trick" them into closing by hitting the dimmer switch, but it wasn't consistent at all.

I thought about it and realized the Charger guys had to have these same issues.... I found out they were just replaced the factory headlight relay with a Tyco unit.

The relay is located (on my 70 300 anyway) on the left of the dash, next to the A/C duct. There's a circuit breaker and connections to the door motors and headlight switch.

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The new relay needs to be wired like this:

View attachment 131442

Same relay etc. as above. I decided not to splice into the wiring and use the existing connections. I used a couple ring connectors and some spade connectors with an insulator.

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I wrapped the connections with 3M splicing tape.

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The relay was mounted under the dash on the steering column support.

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Excellent write up, this is definitely going on my to do list! Quick question though, from your pictures it looks like you used 4 relays, or is there an extra one for something else?

 

[Big_John]

Excellent write up, this is definitely going on my to do list! Quick question though, from your pictures it looks like you used 4 relays, or is there an extra one for something else?

Three relays. One for the headlight doors and two for the headlights.

The "extra" relay was for something else that I was trying.

 

[thethee]

Would a 30A fuse be okay instead of the circuit breaker?

 

[Big_John]

Would a 30A fuse be okay instead of the circuit breaker?

No.

The circuit breaker is there to protect if there is a problem (obviously), but it also will reset itself if the problem goes away. This is a feature you want in a headlight circuit.

A headlight failure could spike the amperage draw and "pop" the fuse. The failure and spike is momentary, but the fuse going out isn't going to do anything until you change that fuse. The breaker will reset itself and you have lights again. Important stuff driving out on a dark country road.

People disagree on this, but remember that your car was built with a circuit breaker in the headlight switch rather than a cheaper fuse.

 

[thethee]

Understood, I'll see if I can get some circuit breakers over here. Thank you John

 

[3175375]

No.

The circuit breaker is there to protect if there is a problem (obviously), but it also will reset itself if the problem goes away. This is a feature you want in a headlight circuit.

A headlight failure could spike the amperage draw and "pop" the fuse. The failure and spike is momentary, but the fuse going out isn't going to do anything until you change that fuse. The breaker will reset itself and you have lights again. Important stuff driving out on a dark country road.

People disagree on this, but remember that your car was built with a circuit breaker in the headlight switch rather than a cheaper fuse.

I may point out that I believe @Big_John is referring to resettable circuit breakers, as ‘regular’ circuit breakers trip and have to be manually reset. Resettable circuit breakers are designed to re-engage automatically or be reset electrically.

 

[thethee]

I try to use it as little as possible but sometimes amazon has exactly what you need. Got some relays (bosch), connectors, and circuit breakers coming my way. Might be a while but will let you know how it turns out

 

[Big_John]

I may point out that I believe @Big_John is referring to resettable circuit breakers, as ‘regular’ circuit breakers trip and have to be manually reset. Resettable circuit breakers are designed to re-engage automatically or be reset electrically.

That is correct.

The circuit breaker shown in my first post is the commonly available resettable type that just about every auto parts store carries. I've even seen these specific breakers used for the cigar lighter circuit in some cars.

I'm sure there are some out there, but I can't remember ever seeing a breaker built for automotive use that is manually resettable.

 

[Big_John]

I try to use it as little as possible but sometimes amazon has exactly what you need. Got some relays (bosch), connectors, and circuit breakers coming my way. Might be a while but will let you know how it turns out

Amazon has become my "go to" for just about everything. I'll even get the part number from Rock Auto and then look it up on Amazon and compare prices. Since there's now a RA warehouse (United Auto Supply) in town, RA sometimes gets me stuff almost as fast as Amazon, but I defer to Amazon for their return policies and since there's now an Amazon warehouse in town too, most stuff is here in a day.

 

[thethee]

Amazon has become my "go to" for just about everything. I'll even get the part number from Rock Auto and then look it up on Amazon and compare prices. Since there's now a RA warehouse (United Auto Supply) in town, RA sometimes gets me stuff almost as fast as Amazon, but I defer to Amazon for their return policies and since there's now an Amazon warehouse in town too, most stuff is here in a day.

The items that need to come from the US I get through RA, their shipping rates are by far the best for me.

Things that aren't specific for my car I try to get from a European source, preferably local even. You know, with import tax and shipping and such. But sometimes amazon.nl has the exact items, for cheaper, and when I ship it to a depot shipping is free. Add the return policies and it's hard to ignore

Amazon.com however, has not been my friend. The interface between those sites is for some reason abysmal.

 

[Gerald Morris]

If you want a manual reset 12VDC circuit breaker, get a marine breaker. M-Series Miniature Circuit Breakers These look well suited to automotive uses. Might try a couple myself.

Here's a generic thermal overload breaker, max DC voltage 28 V, I don't like thermal breakers, but it should do nicely for automotive circuits: ETA 25A 25 Amp Push Button Breaker Max of 250vac/28VDC W03

 

[Gerald Morris]

The items that need to come from the US I get through RA, their shipping rates are by far the best for me.

Things that aren't specific for my car I try to get from a European source, preferably local even. You know, with import tax and shipping and such. But sometimes amazon.nl has the exact items, for cheaper, and when I ship it to a depot shipping is free. Add the return policies and it's hard to ignore

Amazon.com however, has not been my friend. The interface between those sites is for some reason abysmal.

Stick w Euro sources whenever possible bro! Cheap asiatic garbage FLOODED the market HERE, and Jeff Bezos has done MORE than just an average share of the flooding. Old stock U.S. made stuff still can be found in the Colonies, but the new stuff stinks.

 

[3175375]

That is correct.

The circuit breaker shown in my first post is the commonly available resettable type that just about every auto parts store carries. I've even seen these specific breakers used for the cigar lighter circuit in some cars.

I'm sure there are some out there, but I can't remember ever seeing a breaker built for automotive use that is manually resettable.

I have seen the manually resettable breakers in Bruno, my 2010 38’ Holiday Rambler Endeavor diesel pusher.

 

[Big_John]

I have seen the manually resettable breakers in Bruno, my 2010 38’ Holiday Rambler Endeavor diesel pusher.

In the truck part or the "house" part?

 

[3175375]

In the truck part or the "house" part?

I believe that it’s in the house part.

 

[thethee]

One last question for now, probably overthinking it, but how strict are the wire gauges for this? You mentioned 8 gauge and 12 gauge but I'm dealing with metric over here

 

[bnz84]

Concerning relays and circuit breakers I am intrigued by this combo....

Amazon product ASIN B01NBAO1SA
Amazon product ASIN B092CDM26G

 

[3175375]

Concerning relays and circuit breakers I am intrigued by this combo....

Amazon product ASIN B01NBAO1SA
Amazon product ASIN B092CDM26G

I just ordered this:

Jamgoer 12-Slot Relay Fuse Block Holds 6 ATC/ATO and 6 Relays with 6 Blade Fuses 5 Relays and 1 12V 4 Pin Relay and Metallic Pins Spade Terminals Universal Waterproof Box for Auto Marine Boat Truck… https://a.co/d/dhwpcZs

I like the packaging.

 

[Big_John]

One last question for now, probably overthinking it, but how strict are the wire gauges for this? You mentioned 8 gauge and 12 gauge but I'm dealing with metric over here

Just round up to the next size. Rule of thumb would be to never go smaller.

American Wire Gauge to Metric Conversion Table | Electrical Car Services