I have researched a bunch of old threads on horn issues, but haven’t found anything similar to my situation. Previously, the horn button on the turn signal stalk didn’t work and the PO had hacked the wiring harness on the turn signal assembly to install a button. I undid his handiwork and replaced the turn signal assembly after I found the steering column threads were stripped. After replacing the turn signal assembly. the first time I pressed the stalk, the horn worked but sounded weird. It sounded like maybe only one of the horns was working.
Tonight I removed each horn, cleaned off the electrical connectors and test each one individually on my bench. Each horn (High and Low) sounds like they should and was loud with my 12v test unit. Under the car, I tested each of their ground connectors and found they are getting a good ground. I tested the wiring that spans between the two horns and it showed continuity. I then tested each horn individually by disconnecting each one separately and each sounds about right.
When wired together, the sound does not appear to be correct with the high and the low note, they sound somewhat muted. Could this be the relay? Any other places to check?
If it is the relay, on a Series 2 where can I expect to look for it?
Sounds like (bad pun intended…) you have high resistance somewhere in the circuit preventing sufficient voltage/current from getting to the horns. It could be bad relay contacts or other contact resistances elsewhere in the circuit. EDIT The relay is in front of the battery compartment on the vertical mud shield:
I’d start by disconnecting the horns and measuring the voltage at the horn connectors to see what’s actually getting there. If low then start working your way backwards through the circuit.
I think you’ll find that the relay on the picture frame is the cooling fan relay - it is on my Series 2. The horn relay is located on the rear of the driver side front wheel splash panel, together with the alternator relay and A/C Relay (if fitted). I agree that the relay contacts could be the source of the problem. It would be easy to bypass it as a test before going to the trouble of removing it and opening it up.
It might be best to check the voltage drop whist the horns are in circuit and sounding. That way the load current will produce a voltage drop, if there’s one to see, with a multimeter. As you indicate this may be poor contact in the horn relay, or poor earth, or poor connectivity at contacts. Paul.
If I recall correctly: The turn signal stalk grounds the relay magnet circuit. This action activates the relay higher amp circuit to close, sending power to the horns.
Find the relay on the fender, pop the top, clean the “points”.
So I took the relay out, cleaned up the wiring connectors and took it apart to clean the contacts. As soon as I reconnected the battery the horn sounds and won’t stop unless I disconnect the battery. What’s up, did I do something?
Never mind. As I tell my wife every time she has a problem with her smartphone, computer, and DVR “it’s a user error”. It helps if you plug the wires in correctly… all seems well now.
Hey Bob, Your funny like a MINI GTJOEY! It great to see you jumped in all the way…
All those horns if ORIGINAL BY NOW ARE BORDER TERRIBLE.
Its not the horns fault, they are old and the blatter as I call it are worn out. Sometimes they work sometimes maybe.
OLD XKs had the RED replacement horns, crisp, sounds great and louder and draw 85% less energy!
They do not look correct BUT who is looking over there.
Good luck.
GTJOEY1314
KEEP GOING…
P.S I still have my factory wiring book for series 2 only, call or email if you need colors, series 2 is all by itself and I had mine for close to 30 years.
Joey- the horns are very much rebuildable to a fully working state. Mine were in really poor shape but after cleaning them up, adjusting, making new gaskets, and reassembling they both work really well.
Doug I respect your efforts. I must be getting old, I did that years ago as well but…
I put those in a draw for posterity paid 40 dollars? for the xk horns and can BLAST people off the road like the rest with no power draw and a micro chip!
But thats me…no wha wha wooo wooo cough.
Just clean horns.
Having fun.
GTJOEY1314
Thanks guys. I cleaned the relay and got them working acceptably well for now. Ultimately I will replace the relay and/or the horns.
Today I’m at the Jaguar Owners Association of North Texas Concours. Given that the Jag is new to me for only three weeks, I only entered it in the Driver category not championship. There are 6 Jags (E-Types) here and 4 are entered as Championship, 1 as Special, and me alone as a Driver. Wish me luck…LOL
Ut oh…Take a couple Advil, some will kill you because its not 100 percent original, then the second wave comes by and kills you because stock is no good. Then lastly if your driving under your own power, most will faint that dust and air particles touched the paint:)
Other than that have a great time!
gtjoey1314
