Morning Mk2daz Do you mean the black and brown cables that push into the steering wheel. I haven’t shorted these together yet. I wanted to get a decent wiring diagram before I started shorting across stuff. The brass lever under the steering wheel looks brand new. It’s had horn issues before looking at the past MOT’s. The relay works out of the car as I put 9v across it and it clicks. I’m pretty sure the earth side of the steering wheel to the fuse box is the issue. Will be looking at it tonight.
if the little earth from the rack to the chassis is ok, it could be the ignition live for the horn relay which is fed from fuse 18: https://clubgti.com/forums/index.php?threads/fusebox-faq.219775/ fuse 16 powers the ignition live on the horn itself, but that wont stop the relay clicking. 53 is a standard pattern 4 terminal relay so aftermarket jobbers will do fine if you suspect its that
Hi Rubjonny I’m pretty sure the steering rack earth is good. It was a complete pain to get to with the probes. It’s definitely earthed. What is the purpose of the blue/brown cable that the brass lever under the steering wheel is linked to. Is that an earth or voltage cable? https://flic.kr/p/2ocZHCR It’s the 3rd cable from the left. I’m going to have a proper look tonight with the boy. I’m still thinking it’s switch side to the fuse box. Will post more later. Thank you
Just a quickie The black cable inside the steering wheel, should that be a live? https://flic.kr/p/2ocFEPH I disconnected the earth in the pic to run some checks. unfortunately I’m not much of a motorcar mechanic but more of an aircraft technician .
the brown/blue goes off to the horn relay, if you earth that it should click in a nutshell: relay earth pin -> brown/blue wire -> tab on stalk -> slip ring -> button -> column -> rack -> brown wire -> chassis
So I earthed the blue/brown cable, turned on ignition and no click whatsoever. So I decided to do a continuity check of the cables: blue/brown cable to front of relay socket 1/85 - all good brown cable to front of relay socket 2/30 - all good Checked for ignition live at 4/86 - 12v Checked for ignition live at L2 - 12v The problem I have checking the front of the fusebox with 53 removed is getting something to fit into the spade slot. I don't have any spade connectors as yet to make up a test lead. This is all pointing to a dodgy relay even though I checked it out of the car. I'm going to throw another relay in to see if this works. Other than that, what's the best way to bypass the relay? The other checks I did was to make sure the buttons ground earth when pressed. I took the wheel off and put my probes either side of the wheel (brass ring and inner earth. When the button was pressed I got good continuity. Let's see if a new relay works. *Just looking over the diagram the best check would've been press the button and check for earth at socket 85 on the front of the fusebox...* Never mind...
Actually just studying the wiring diagram I shouldn’t be getting 12v at the pin of L2 on the loom at the back of the fuse board. I need to double check this again. That should be the earth line when the relay switches over. I wonder if the connectors in the engine have been mixed up or the connectors on the horns? Or one of the horns is shorting?
Although the relay clicks, it may be the load carrying contacts that are kaput, not making the circuit. If you Bridge those 2 terminals in the relay holder in fusebox the horn should sound. You may get a 12v reading as the supply to horn will go right back the other wire to there, which is basically how an alternator light on dash works, it gets ground from the non rotating alternator as no voltage is being produced, then when engine running 12v made by alternator is fed to dash light and so with the ignition on it has 12v on either side of bulb and so doesn't light, if that makes sense. Have you put a meter on horn wires in bay and seen if get voltage when pressed, and check to 12v and earth to see both wires functioning, and do both horns work, ones not shot and so putting too much draw of current to make other work?
the poverty spec cars dont have a relay, instead it has a bit of metal pushed into the 87/85 terminal sockets on the fusebox, then the horn is earthed directly by the button. the dual tone horns often dont like working like this though, on my old 1.6 driver I fitted a single tone horn to replace the embarrassing standard fit meep horn and it would only work ignition on, once I fitted a relay it was all good. but yeah with ignition on, if you jump pin 30 to 87 with a loop of wire the horn should sound as you'll be shorting the earth pin from horn direct to earth probing L/2 or 87 on relay socket with ignition on will result in 12v as you have completed the horn circuit through your multimeter and so you'll see voltage. if you unplug horn you can do a continuity check from L/2 to horn brown/black, but the fact you see 12v shows you have something. it could just be a corroded connection in the bay, the horn wiring plugs into the main headlight loom near the passenger headlight using an unsealed spade housing so corrosion often builds up
Thanks for all the continued help guys, really appreciate it. The boy is loving the car but not sure about the old man haha! It looks like the weekend will be good to get back on his car. I have a rear washer motor to slave in as well as trying to get the rear wiper motor functioning but that's not as important as the horn. Our problem is the location of the second horn. It's a bit of a nightmare to get to. We don't have access to a ramp so I guess jacking it would be best with a trestle. We'll get it working! Thanks Guys Paul & Dawson.
Well it's all fixed! Slaved a new 53 relay in and it beeps. Thank you for all your help in resolving the issue. Probably be posting rear wiper not working soon haha. That's the last electrical issue with the car. I've not even looked at that one yet but suspecting the motor as the relay clicks when the lever is moved forward. Thanks again guys.
good news start looking in the rubber boots where the wiring comes into the tailgate, often goes there. the tailgate wiring plugs in on the left side near the rear light somewhere so you can probe there as well. the grey/black wire should have ignition live, and the green/black pulsed live when the relay clicks. brown is earth obv
Will get looking this weekend. Fixed the rear washer motor last night too. Put 12v across the motor and nothing so slaved another motor in and that's all good. Will get a good look at the wiper motor shortly. Hoping it's another easy fix.
Ugh! The boy informs me the horn has stopped working again.. Something must be blowing the relay. Will check fuses first.
