Headlight relays

Larry

True Classic
Headlight relays were installed in my '79 X1/9 by a previous mechanic that worked on the car, but the headlights have never really been very bright even though I'm running Hella H4 with 55W/60W bulbs.

The wire that was installed that runs from the headlight relay to the battery is too short and that caused (either the mechanic or someone else who worked on the car) to move the positive battery connection to the passenger side of the car and to switch the battery as well. I'll be replacing the positive battery connector so I'll be putting the car back to stock with the positive battery terminal located near the center of the car (as opposed to along the passenger side as it is now).

The wire that's run between the battery and the headlight relay (it's yellow) looks to be about 18 gauge. It runs inside of the weatherstripping and pops out near the headlight area and then runs through a grommet to a crimp-on connection that runs to a (blue wire) that has a fusible link that runs to the relay (the fusible link is disconnected in the photo).

I assume there's a voltage drop at the crimp-on connection between yellow battery lead and the blue fusible link which is making my headlights not quite as bright as intended.

I'm going to replace the wire with a continuous run - either from the battery or a terminal block mounted on the firewall - to the headlight pod where the relay is located.

My questions:

1. I have some 12 gauge black wire - is that good enough or should I go for something like say 8 or 10 gauge instead? As a side question - I know color of the wire doesn't really matter, but do people usually use say yellow for this type of work? The black wire is from a small spool I've had in the garage for years.

2. The photos I've seen of Bob Brown's and other headlight relay kits shows 2 relays in the headlight pod. So far, (I've only checked one side) but I only see 1 relay. Assuming there's no relay on the other side, is the 2nd relay advisable - I assume one is for the low beams and 1 is for the high beams?

3. Is it okay to solder a fusible link between the line running from the battery to the relay? Or is there a better or more efficient way to do this?

Thanks,

Larry
 

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Before you do anything else, clean the ground connections, see if that improves the lighting any.
1. I have some 12 gauge black wire - is that good enough or should I go for something like say 8 or 10 gauge instead? As a side question - I know color of the wire doesn't really matter, but do people usually use say yellow for this type of work?
12 gauge will easily carry 20 amps or 240 watts here, but I wouldn't do anything smaller and would use 10 if it were available.
Of course the color doesn't matter, but it's good practice and the next owner will thank you if you use a color that looks like unswitched hot (brown or red) instead of ground (black or green).
2. The photos I've seen of Bob Brown's and other headlight relay kits shows 2 relays in the headlight pod. So far, (I've only checked one side) but I only see 1 relay. Assuming there's no relay on the other side, is the 2nd relay advisable - I assume one is for the low beams and 1 is for the high beams?
The high beam and the low beam are separate circuits so you need a minimum of two relays, one for each. You can do the Bob Brown style, with four relays total (two for left low and high, two for right low and high) or you can use two relays in one pod with wires to the other headlight bay, one controlling both high beams and the other controlling both low beams. If you go with two relays, the stock headlight connector in the other bay won't be connected at all..

I've done it both ways. With just two relays there is a greater chance that a failure will leave you with no headlights at all.
3. Is it okay to solder a fusible link between the line running from the battery to the relay? Or is there a better or more efficient way to do this?
An inline fuse holder and good crimp connections.
 
That sir is a bit of a horror show.

Lots of connections, low quality parts, undersized wire, poorly routed wires and questionable assembly. I can see why it isn’t delivering additional lighting. Wires should not be routed inside a seal as was done here.

I would start by removing it and starting/making it over, it is not hard and will yield much better results.

Yes there should be at least two relays, one for low beam and one for high beams. If the relays are in the pod area, they should be either waterproof or in a water proof box. Connections should be minimized and wire gauge as heavy as is reasonable for the load placed (110 watts assuming normal bulbs and not aircraft landing lights) thus 10 or 12 gauge depending on what you can lay your hands on and how you choose to approach the power distribution.

I would start with replacing your battery connector or at the least, making or buying from an auto parts store a single high quality ring connection using an 8ga wire like this 8DAE03EB-0CBF-4AE7-8D95-ADF0F6B1504B.jpeg to go from the battery to a fuse block like this: https://www.amazon.com/Blue-Sea-Systems-Blade-Block/dp/B01BV1MS1K?ref_=bl_dp_s_web_5638639011&th=1
C1D70AF8-6EFD-4199-8BD9-7FAAD1133C65.jpeg
This will give you the two connections you need for the two headlight relays you need and two more for future projects like the wiper relays you will be adding in the near future (hint, hint :) ) The nice thing about this is the fuses are in one place and everything is covered. This can be put near the battery just above the wiper fluid reservoir or alongside it.

Buy two (or four) standard relays capable of 30 amps each, each with two terminals to carry power to the headlights, often referred to as SPDT (single pole, dual throw) so each headlight would have a dedicated wire going to the low beam and the high beam. I would mount them near the battery but if you choose waterproof relays and relay blocks they could go to the headlight pod. https://www.amazon.com/ONLINE-LED-S...30+amp+relay&qid=1564141857&s=gateway&sr=8-10
819EDD51-6597-46F8-A561-10157001F97B.jpeg
Alternatively you could use four relays (preferably water proof), two in each pod to have a dedicated relay for each headlight’s low beam and high beams.

Now depending on your strategy, you could be running either two wires carrying fused power to either the relays mounted in the trunk and then two wires or four wires from the relays to the lighting pods or just the two fused power wires to the pods to power the relays located there. Either way, the wires should run inside the plastic cover on the passenger side floor/side wall of the frunk. This is where the standard wires run, they are protected and there are already grommets to go into the lighting pod areas.


I apologize I need to run to work and have a concert to go to this evening so I won’t be able to finish this until tomorrow morning.

Karl
 
If you are buying supplies like connectors, relays, wire and such locally, my advice is go to a local NAPA store for the items with their traditional electrical brands, Balkamp, Belden, etc. VASTLY superior to AdvancePepZone chain store stuff and most eBay stuff.

Example below: 10 ga eBay wire vs 10ga Belden wire from NAPA.
IMG_1899.JPG
 
Agreed, getting parts from non cheapo sources (much of Amazon is cheap crap, images shown were to illustrate) from reliable brand names would be the best choice.

Blue Sea Systems makes good stuff and can be found locally at boat supply stores as an alternative.

Relays, connectors and wire are all items whose quality are often suspect.
 
That sir is a bit of a horror show.
I completely agree, no offense to whomever did the original installation but it looks pretty bad to me. I'd start over and do it much better by following the advice of those already posted. Your 55/60 W Hella's should be very bright, I think the problem is with the installation of that add-on harness.
 
That sir is a bit of a horror show.

Lots of connections, low quality parts, undersized wire, poorly routed wires and questionable assembly. I can see why it isn’t delivering additional lighting. Wires should not be routed inside a seal as was done here.

I would start by removing it and starting/making it over, it is not hard and will yield much better results.

Yes there should be at least two relays, one for low beam and one for high beams. If the relays are in the pod area, they should be either waterproof or in a water proof box. Connections should be minimized and wire gauge as heavy as is reasonable for the load placed (110 watts assuming normal bulbs and not aircraft landing lights) thus 10 or 12 gauge depending on what you can lay your hands on and how you choose to approach the power distribution.

I would start with replacing your battery connector or at the least, making or buying from an auto parts store a single high quality ring connection using an 8ga wire like this View attachment 23729 to go from the battery to a fuse block like this: https://www.amazon.com/Blue-Sea-Systems-Blade-Block/dp/B01BV1MS1K?ref_=bl_dp_s_web_5638639011&th=1
View attachment 23728
This will give you the two connections you need for the two headlight relays you need and two more for future projects like the wiper relays you will be adding in the near future (hint, hint :) ) The nice thing about this is the fuses are in one place and everything is covered. This can be put near the battery just above the wiper fluid reservoir or alongside it.

Buy two (or four) standard relays capable of 30 amps each, each with two terminals to carry power to the headlights, often referred to as SPDT (single pole, dual throw) so each headlight would have a dedicated wire going to the low beam and the high beam. I would mount them near the battery but if you choose waterproof relays and relay blocks they could go to the headlight pod. https://www.amazon.com/ONLINE-LED-S...30+amp+relay&qid=1564141857&s=gateway&sr=8-10
View attachment 23730
Alternatively you could use four relays (preferably water proof), two in each pod to have a dedicated relay for each headlight’s low beam and high beams.

Now depending on your strategy, you could be running either two wires carrying fused power to either the relays mounted in the trunk and then two wires or four wires from the relays to the lighting pods or just the two fused power wires to the pods to power the relays located there. Either way, the wires should run inside the plastic cover on the passenger side floor/side wall of the frunk. This is where the standard wires run, they are protected and there are already grommets to go into the lighting pod areas.


I apologize I need to run to work and have a concert to go to this evening so I won’t be able to finish this until tomorrow morning.

Karl

**** show is how I've termed it myself Karl. There are other modifications as well done intending to improve the car, but sadly, they didn't quite work out the way it was intended. Fortunately, the electrical modifications seem to have been just the positive battery connection (from my Odd Running thread) and this wiring for the headlight relay.

Thank you for what you've written and the part recommendations, but before you find time to add to it, I need to let you know that you triggered a memory and I found my Bob Brown Insertable Headlight Relays. I vaguely recalled having bought a set some number of years ago and I was able to find it - right where I thought it would be - in the bottom drawer of the china cabinet. I probably bought it for my (now) ex-'86, but now I'll use it for my '79.

I'll definitely pickup a fuse block. I no longer have a wiper fluid reservoir - instead I have a 10-watt amp located there, which I would love to remove. But I'll find a nice spot to put the fuse block in place. And I'll get some red or brown 8 and 10 gauge wire.

I like the idea of wiper relays. I usually just use Rain-X for heavier rains, but anything to make the wipers a bit peppier has to be good.

I would eventually like to run the power from the fuse block to the fuse panel under the glove box, but I'm (a) not quite certain how to do that and (b) need to figure out what was done with the dashboard instruments.

Larry
 
If you are buying supplies like connectors, relays, wire and such locally, my advice is go to a local NAPA store for the items with their traditional electrical brands, Balkamp, Belden, etc. VASTLY superior to AdvancePepZone chain store stuff and most eBay stuff.

Example below: 10 ga eBay wire vs 10ga Belden wire from NAPA.
View attachment 23733

Thanks Dan. For some home wiring projects, I picked up a small spool of wire from Home Depot. What do you think of the quality of their wire compared to NAPA? Sadly, I've become acutely aware of the quality at AdvancePepZoneOReilly.

Larry
 
I completely agree, no offense to whomever did the original installation but it looks pretty bad to me. I'd start over and do it much better by following the advice of those already posted. Your 55/60 W Hella's should be very bright, I think the problem is with the installation of that add-on harness.

The mechanic isn't on XWeb so no worries about offending him.

The amusing thing is many years ago, he sold me a HID light kit after showing me how much brighter it was than the Halogen upgrade he'd done to the car. I haven't installed those HID lights yet. I'll redo the mess that's there and see how the lights are.

Larry
 
every time I see crimp connectors I cringe knowing those will be a problem, not if, but when.
Well in defense of the mechanic that installed them, the crimp connector was in the headlight pod wrapped in a decent amount of black electrical tape that ran about 2" to either side of the connection.

Would you recommend a bullet connector instead or ??

Larry
 
solder and heat shrink. best to get insulation less connectors, but even those connectors can be ok. remove the insulation, solder them and cover with shrink wrap.
 
Solder vs crimp is one of those topics like oil that are endlessly debated. Me? the only soldered connectors I would use are the silly expensive ones intended for marine use - a salt-water boat is about the only thing that gets more vibration and corrosion than a car.

But no matter what you do.... it’s impossible to use too much heatshrink.
 
(( well, strangely enough, you are not allowed to solder on an airplane they require a special crimp) (the harmonics of their vibration will break solder joints)
 
(( well, strangely enough, you are not allowed to solder on an airplane they require a special crimp) (the harmonics of their vibration will break solder joints)
And OEM wiring harnesses use crimps not solder too.

Good crimps plus heatshrink is IMO the way to go.
 
Well in defense of the mechanic that installed them, the crimp connector was in the headlight pod wrapped in a decent amount of black electrical tape that ran about 2" to either side of the connection.

Would you recommend a bullet connector instead or ??

Larry
NAPA carries (among other styles) the type that combines a crimp for the physical connection with heat gun activated shrink and seal to make the wire<->connector joint waterproof.
 
Thanks for the suggestions and opinions. I figure I'll look at what was used on the car already and get something else.

But to replace the positive battery connection. I'm planning on cutting the wire beyond the part that was bent for the past 20+ years, tinning the ends and then putting the ends into either 1 or 2 copper crimp connectors and then into a new battery connection. But I'm having more trouble than I expected in finding a copper crimp connector in large enough a gauge.

Is there a different recommended way to do this?
 
There are the newer clamp connectors which can accommodate multiple conductors with a screw clamp for each one.
This one is found on some modern cars and allows attaching other wires to the positive: https://www.amazon.com/BT4Z-14450-A...battery+clamp&qid=1564532210&s=gateway&sr=8-5

https://www.amazon.com/BT4Z-14450-A...attery+clamp&qid=1564532464&s=gateway&sr=8-36

This one is a bit light gauge:
https://www.amazon.com/Keadic-Termi...attery+clamp&qid=1564532210&s=gateway&sr=8-17

This one is a bit better
https://www.amazon.com/Cllena-Milit...attery+clamp&qid=1564532324&s=gateway&sr=8-21

You should be able to find large copper crimp connectors fairly easily

https://www.amazon.com/SELTERM-Gaug...mp+connector&qid=1564531874&s=gateway&sr=8-43

And then there is this style which I am not completely a fan of:
https://www.amazon.com/InstallGear-...uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl

And then there is this piece which could effectively give you a fuse box and multiple heavier gauge connections to the rest of the cars secondary circuits (brown wire mod etc) and is used on A4 VWs, it lives on top of the battery:
https://www.amazon.com/Runmade-Fuse...jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==
 
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There are the newer clamp connectors which can accommodate multiple conductors with a screw clamp for each one.
This one is found on some modern cars and allows attaching other wires to the positive: https://www.amazon.com/BT4Z-14450-A...battery+clamp&qid=1564532210&s=gateway&sr=8-5

https://www.amazon.com/BT4Z-14450-A...attery+clamp&qid=1564532464&s=gateway&sr=8-36


This one is a bit better
https://www.amazon.com/Cllena-Milit...attery+clamp&qid=1564532324&s=gateway&sr=8-21

I quite like these. The Cliena one looks intriguing.

You should be able to find large copper crimp connectors fairly easily

https://www.amazon.com/SELTERM-Gaug...mp+connector&qid=1564531874&s=gateway&sr=8-43

I wasn't considering an eyelet. The terminal connector I picked up doesn't accommodate that so I was thinking along the lines of a hollow tube (essentially), but I can easily alter my thinking (as well as return the part).


And then there is this piece which could effectively give you a fuse box and multiple heavier gauge connections to the rest of the cars secondary circuits (brown wire mod etc) and is used on A4 VWs, it lives on top of the battery:
https://www.amazon.com/Runmade-Fuse...jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

This is very intriguing. Excuse my ignorance, but the bottom photo looks like there are fuses between the nuts? If that's the case, does that mean 2 circuits could go onto each nut so there would potentially be a 50A or 110A fuse on them?

Right now, the BWM appears to go straight to the battery. After Concorso week is over, I can revisit it and move the BWM to its own connection if need be. I'm hesitant to change things out of fear of finding out other surprises.

Larry
 
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