Headlight relays

Larry, I'm with Karl. I'd simply yank everything out and toss it. Then start from scratch and build a proper set up with quality parts and a good design. Always use fuses, relays, appropriate gauge wire, good connectors, insulation/heat shrink, etc. If it helps, look online or in books for ideas on creating automotive electrical harnesses/wiring systems.

In the long run it will be much faster to do, easier to understand, likely less expensive (after having to redo the redo a couple of times), and work much better/more reliably. How much will the car be worth if it burns to the ground due to a electrical short? Do you want operating headlights, every time? I'm not being sarcastic and certainly not questioning your thoughts, I'm just speaking from the experience of doing things different when I was younger and didn't know better.

Gad, I must be getting old if I'm giving the "do it the right way" speech...only old farts say those things. :(
 
Larry, I'm with Karl. I'd simply yank everything out and toss it. Then start from scratch and build a proper set up with quality parts and a good design. Always use fuses, relays, appropriate gauge wire, good connectors, insulation/heat shrink, etc. If it helps, look online or in books for ideas on creating automotive electrical harnesses/wiring systems.

In the long run it will be much faster to do, easier to understand, likely less expensive (after having to redo the redo a couple of times), and work much better/more reliably. How much will the car be worth if it burns to the ground due to a electrical short? Do you want operating headlights, every time? I'm not being sarcastic and certainly not questioning your thoughts, I'm just speaking from the experience of doing things different when I was younger and didn't know better.

Gad, I must be getting old if I'm giving the "do it the right way" speech...only old farts say those things. :(

Thanks for this and thanks @kmead for the advice.

I might have seemed a bit obstinate about the work that needs to be done because I've been thinking "it's worked for over 20 years - including the 19 I've owned the car." But then I remembered, the car very rarely is driven in the rain - partly because the weather stripping over the driver's side window leaks so I get water dripping into the car - but also out of concern a distracted driver will take the car out. I'm in Northern California and fortunately, we don't get occasional summer showers as other parts of the country.

And I haven't washed it with water for years - I use the waterless car wash products - partly out of concern of water accumulating somewhere I'd prefer it not wind up.
 
it's worked for over 20 years - including the 19 I've owned the car
Actually I did not realize that, I thought it wasn't working well. So now it makes more sense where you were coming from. Often it is easy to get going in one direction and just keep going that way, even after it seems to not be working (at least for me). :(
I suppose another way to look at it is these components are now over 20 years old, so it might be time to replace them. Electrical stuff ages, gets corroded, increases resistance, and fails. This affords you the opportunity to make it much better with an improved design. ;)
 
Actually I did not realize that, I thought it wasn't working well. So now it makes more sense where you were coming from. Often it is easy to get going in one direction and just keep going that way, even after it seems to not be working (at least for me). :(
I suppose another way to look at it is these components are now over 20 years old, so it might be time to replace them. Electrical stuff ages, gets corroded, increases resistance, and fails. This affords you the opportunity to make it much better with an improved design. ;)

There are some issues with it. The car's not being able to start was due to (this is the current theory) a vacuum leak when the car is hot that causes it to idle at about 2000 RPM. But in trying to track that down.... In the 19 years, I've put about 80,000 (of the 335,000 miles the car has on it) miles in the time I've owned it so while it does get driven a lot, you can say it also doesn't. But you have a good point because things do age and like us, increase resistance.
 
It is never easy to unwind work previously done, this one seems especially odious. I apologize for reiterating but you really need to start over by identifying what you have and planning a means of fixing the problems you find. Don’t try to reuse components as the quality of the previous mechanics work will affect your work and his work was not good.
No apologies necessary. I've had my hands full with other issues so my posts have dragged on longer than I would have liked. I don't mean to seem as dense as I probably do (hopefully only at times).

The car already has a horn relay so they used the existing horn wire. You can’t use one relay for more than one task, ie turning on the lights and running the horn on demand.

From what (little?) I know, the standard horn was replaced by an air horn so that's an air compressor in the photo. Most air horn kits I've seen recommend using a relay so perhaps that's why the relay is there? And yes, running multiple things off a relay is obtuse. But I can imagine he thought how often do you use the horn when looking down a dark road at night. From that perspective, what he did makes a little more sense (not a lot more).

Putting unprotected relays into the headlight pod is a poor approach as the ones you have are not water sealed units in addition to all the poor connectors used to joint everything.

One can solder and heat shrink but service becomes difficult and there are issues with solder due to vibration breaking the hard joint or the wire to either side of the hard joint.

NAPA sells quality connectors and there is of course the internet. NAPA is your better choice as it is hard to know what you will get from Amazon etc from a quality standpoint.
Thanks. Looks like I'll be making another NAPA run today.

I would add the fuse holder I linked to earlier which gives you four power sources and I would place the new relays next to it. I wouldn’t attach the relays to the battery cover, you are running wire one way or the other so I would install the relays to the structure of the car near the battery.

I've got Bob Brown's headlight relays. While I like the idea of putting the relays near the battery, I was thinking of putting the relays into a plastic box inside the headlight pod as per the kit's instructions. I even removed 2 plastic food storage containers from the kitchen late last night because I can't find Radioshack Project boxers.

I have attached the wiring diagram for the lighting and the horn system below.
 
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of the 335,000 miles the car has on it
PLEASE tell me that is a typo! There cannot actually be a X1/9 with 335,000 miles on it. They simply won't endure that much use. :D

Regarding the relay for the air horns. It is not possible to run two systems (e.g. headlights and air horns) off one relay. They would both come on at the same time, every time either was turned on.

You can find lots of project boxes on line as well.
 
PLEASE tell me that is a typo! There cannot actually be a X1/9 with 335,000 miles on it. They simply won't endure that much use. :D

Regarding the relay for the air horns. It is not possible to run two systems (e.g. headlights and air horns) off one relay. They would both come on at the same time, every time either was turned on.

You can find lots of project boxes on line as well.

Actually there are bunch of Xs with high mileage. The chassis was over structured and the majority of the mechanicals are well made. The engines should last for lengthy periods before a rebuild. The same is true of the twin cam motors.

It really all comes down to proper maintenance and a willingness to drive a small car for lengthy periods.
 
I was being facetious. But that is a lot of miles for any car (aside from a old Mercedes diesel).
 
PLEASE tell me that is a typo! There cannot actually be a X1/9 with 335,000 miles on it. They simply won't endure that much use. :D

Sorry. I hate to say It is a typo.

It should be 335,372. I'm the 4th owner. The 1st owner lived commuted about 170 miles a day for his job for a few years. When I bought the car, it came with a stack of paperwork. There's another X1/9 in this area with over 450,000 miles - and it is (or was) a daily driver.

Regarding the relay for the air horns. It is not possible to run two systems (e.g. headlights and air horns) off one relay. They would both come on at the same time, every time either was turned on.

You can find lots of project boxes on line as well.

Hmm... I'll have to pull the compressor since there are 4 wires on the relay - the power from the battery, the feed to the headlights, the ground and the yellow wire that seems to run from the compressor to the relay.
 
4 wires on the relay
A standard relay for one accessory will have 4 wires; main power to the relay (to feed the accessory when the relay is engaged), switched power to engage the relay, ground wire to the switched side, and the power out of the relay to the accessory when engaged.
 
A standard relay for one accessory will have 4 wires; main power to the relay (to feed the accessory when the relay is engaged), switched power to engage the relay, ground wire to the switched side, and the power out of the relay to the accessory when engaged.

I got it (mostly) figured out. The air horn compressor is not being operated by the relay. I believe it's been wired into things before the relay so the wire running from the horn to the relay is carrying switched power. I just don't know where the tie-in happened - I'm assuming in the fuse box since there aren't any other visible wires.

Given that I can't be sure where / how things were installed, I don't want to start removing and installing new items. Headlights are a nice thing to have and working headlights even more so. I've replaced the existing wire from the battery to the headlight pod, inline fuse, ground wire and wire from the compressor to the relay. A quick fix on my horn button and my horn works again and my headlights work even when the horn button is depressed.

I'll poke around in the fuse box to see if I can determine where the horn compressor is tied into and once I can verify that, I can look into replacing the existing relay with Bob Brown's relay kit.
 
I suppose the main power wire from the battery/fuse box to the relay (for the headlights) could be shared as the main power feed to the horn relay (if the horn has a seperate relay). But the "switched" wires to each (separate) relay need to be different, otherwise everytime the horn is blown the headlights will come on (and vice versa). The ground wires could be split between them as well, provided both relays are grounded for the "switched" circuit.
 
I suppose the main power wire from the battery/fuse box to the relay (for the headlights) could be shared as the main power feed to the horn relay (if the horn has a seperate relay). But the "switched" wires to each (separate) relay need to be different, otherwise everytime the horn is blown the headlights will come on (and vice versa). The ground wires could be split between them as well, provided both relays are grounded for the "switched" circuit.

Sorry for the slow reply. I was getting the car ready for Concorso Italiano and FIAT America's 50th Anniversary weekend of events.

Not sure what was done previously, but I believe the switched wires go from the fuse box to the horn compressor and then to the relay for the headlights. The horn works as do the headlights and neither affects the other.

I have to see if I can figure out how to trace the wire from the horn compressor back to the fuse box to see what was done there.
 
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