I’m a new forum user and I have a novice question: The horn on our 1951 XK120 goes off when turning or telescoping the steering wheel. I know I need to have the column wiring repaired. Until I do, can anyone suggest a simple way for a novice to disable the horn? (it is a bit embarrassing going on short drives randomly blaring the horn, I’m more the quiet type.)
Welcome to the forum Scott, easiest way would be to crawl under the front of the car and pull the wires off the horns and tape then up to insulate them.
Wow, thanks for the forum welcome and the quick response Robin. Ok, I’ll try that – here is to hoping they are connected via pull of flanges vs hard to find screws.
No prob if you google Jaguar XK120 horn and go to images then you will see what you are looking for.
BTW if you go to the top right of the page you will see your avatar, you can click on that and go to preferences and attach a country flag, this helps other listers to know where in the world you are. And yes happy holidays.
You will first have to remove the dome with the screw on top. The electrical connection is by means of two wires. You will find the terminal block on the drawing:
Either type, you remove the wire at terminal W1 and tape it up, should be brown/black.
Or the two wires on terminal C1 and tape them, should be brown/green.
There is a sharp edge inside the steering column stator tube which cuts the insulation on the wires when you move the wheel in and out, and then they touch ground. Mine used to blow fuses when I signaled a left turn.
No, that would also kill the brake lights, reverse lights, fuel gauge and wiper motor.
You are correct on Mark V though, you would lose only your cigar lighter.
Think British. The hot wires go directly to the horns and the horn push completes the ground. The wire to the horn push is getting shorted to ground when you turn the wheel. Trace the wire
Don’t kick me out of the forum but I was about to put a trumpet mute in it to get it to the garage with less drama until I noticed the bar in the flange.
Pat_Harmon - thanks - I found a good spot out here in Los Angeles to get the wires sorted on the steering column, after all this covid stuff, looking to drive around the block now and again to keep the car in running shape - without my neighbors peering out their windows.
Since you are new and we don’t know you very well yet, and I see your wiring is original and probably difficult to determine colors, maybe you would be better to disconnect all of them at the horn relay and tape them so they won’t touch any metal or each other.
Good idea from Rob, but may I add to take photo before, and when you tape them, number the wires and sketch where they came from so you can get the order right when re-installing.
Good idea from Jon. Your future plans might want to include a new wiring harness. I showed a picture of one type of relay, but there are at least two others yours could be, similar but not exactly the same. The bar inside your horn is a screw that holds the trumpet bell in place.
@Rob_Reilly@JonV2 Again a huge help, thank you. I documented the Horn Relay in the attached picture and included the example you sent Rob.
I will:
Disconnect the battery
Disconnect each wire on the relay, labeling as I go
Tape off the ends of each of the four wires to avoid shorts
Reconnect the battery.
There are 4 wires total, the last screw log has two attached.
And yes, original wiring, our plan is to take the car in when covid dies down and have the wiring reviewed/repaired. The car was purchased just before the pandemic and so it has not been looked over properly, we plan to do that post covid.
Ok great, seeing your relay is the same as mine, you would only need to disconnect the two wires at the bottom most terminal, which is terminal C1. They go directly to the horns, so with them off and taped the horns can’t possibly toot.
You might copy this wiring diagram for your shop if you don’t already have one. This is for early OTS to mid-'52 without turn signals. wiring diag W94601A.pdf (90.4 KB)