I have a 72 240z and can't figure out what the heck is going on with this wiring setup in the engine bay. It looks like there are three horn relays and two of them were soddered together and wrapped with electrical tape. There is also another horn relay in the passenger footwell. The horn works. I'm trying to diagnose some broader electrical issues, including no headlights. Anyone have a thought as to what this could be?

When you say "horn relay" are you going by a part # on the relay can? Did you trace them? Is there a possibility that a PO put in the relays for a different circuit than the horn, maybe headlights? This could be an early attempt at Dave Irwin's designed headlight relay harness and maybe the relays are now toast..

There is a headlight plug and play harness mod to remove the load of the headlights from the combo switch stalk in the 240Z's. It's available from thezstore

https://www.thezstore.com/page/TZS/PROD/classic10l/12-4651

Edited August 11, 20195 yr by w3wilkes

Thanks for the feedback w3wilkes. It is actually two horn relays soddered together. They are identical to the other relay in the picture, which I have traced to the horn. I'm thinking you are on to something with this being a potential primitive headlight relay system. I'll be breaking out the multimeter tonight to do some more testing.

I'm also going through 47 years of maintenance and repair paperwork I have on the car to see if anything fits the bill.