Cadillac Horn Mod

[Lutrova]

I've procured a set of four-note Delco-Remy horns from the junkyard and would like to swap them into the Lincoln. Mounting issues aside, my plan is to wire them up in sequence using a stock harness from an Eldorado and run that wire back to the horn relay. Someone elsewhere on the internet felt that these horns will draw maybe 5A each. I believe the stock horn relay is good for 20A and the horns and cigar lighters together are on a 20A fuse.

Should I be upgrading the relay or putting these horns on a larger or separate fuse? Or will the stock wiring support them?

[Kodachrome Wolf]

While not a Box, I fitted the same setup of horns on a '99 CV and used the stock wiring, save for where I removed the connector and spliced a daisy chain of spade connectors together to send power to the horns. Despite the horns also just using a chassis ground, I also daisy chained a ground wire linking them together back to the factory ground, just in-case the support I attached them to wasn't 100%.

Noticed no issues or blown fuses, so I'd say run with what you have.

[gadget73]

do both of the horns live in the same fender on a Towncar or is it one in each side? I honestly don't remember.

[sly]

I'd trigger a relay with the stock horn circuit to drive all of that with a dedicated line from the battery just to cover it. Also... 20A should be peak for 4 horns. I think typical is about 1-3A per horn. But 10A fuse per pair of horns should be about right for covering the electrical requirements.

[DerekTheGreat]

do both of the horns live in the same fender on a Towncar or is it one in each side? I honestly don't remember.

One in each fender.

For the longest time, even when adjusted within resistance spec, both of my horns were pulling over 20A. Aside from the starter motor, I'm pretty sure the horns draw the most current. Perhaps only superseded by the blower motor.

[Lutrova]

I've given the wiring diagram a good deal of scrutiny tonight, and it looks like the stock wiring is very nearly a dedicated circuit just as it is. The only other thing on the same fuse is the dash cigar lighter. Used to light a cigar I could see it drawing some good current, but as a USB/phone charger it's probably not putting much stress on the fuse at all. From the fuse a wire runs out to the horn relay, which can also draw horn power from the anti-theft system, and then out to the separate harness in front of the header panel. There's a connector to this harness right beside the relay. This would probably be the connector to re-pin with the Cadillac horn harness.

If the four-note horns draw no more than 20A, the stock wiring and fuse should be sufficient. If they draw more, then I think you'd not only need to run a separate line from the battery, but you'd also need to beef up the wiring to and from the anti-theft module, which has its own set of fuses.

[GM_Guy]

Just fyi, cadillac uses a 20amp horn relay as well, I wouldn't sweat it.

[Lutrova]

Well that seems pretty definitive then. Honestly not as much work as I expected it to be. Finding the right spot to mount the horns is maybe the hardest part of the operation.

[GM_Guy]

Close to the stock location works real good. When I added horns to my truck I put them down low up front in the engine compartment and the sheet metal has the added bonus of acting like a speaker, definately adds to the overall tone vs just being mounted ahead of the radiator, and it keeps them out of the water spray.

[TheEnglishChap]

My OEM horns are not working on my 87 CP, but there is power running to them (can hear the relay clicking away).
Of course, the locations in the fender is not the easiest to get to - how would you do this?
Not being electrical-minded, how difficult is it to get the A-C-D-F horns installed? If someone has set of instructions - that would be great!!
Thanks!!

[sly]

The horns have a single wire going to them and are grounded through the case/bracket. Each side of the car you just need to unbolt the item in the way and move it enough to get at the horn. Battery needs to be removed on the passenger side to get at that horn and the coolant/washer tank unbolted from the car and just moved over a bit to give enough access for the driver side. Make sure each one is bolted down properly and the contact points are not corroded. Also, pull the connector off the horn and verify power at the horn. If no power at the horn, the relay may be bad. If you do have power, try cleaning contact points for the bracket and plugging the horn back in with everything bolted down snug and try again. If still nothing, then yeah... new horns needed. You can replace with like (dual tone - one tone per side) or modify to your desired pedestrian scaring levels.

[TheEnglishChap]

Thank you sly!
"... desired pedestrian scaring levels." - funniest thing I have read!

[TheEnglishChap]

The Declo-Remy four note horns arrived this morning - yay!
Now for the part I am going to hate... wiring them in.
1. Is there a particular order they need to be mounted?
2. I was planning on mounting them behind the grill in a row. Can I run LH & RH original fender connectors to each pair?
3. Any other useful tips or advice would be most welcome!

[sly]

1: No.
2: Yes.
3: just use 1/4 spade connectors to connect to the original connectors and wrap with heat shrink or electrical tape. If the kit requires grounds, just run the grounds to the brackets and bolt them to something metal.

[massacre]

Great advice here ^^^