Hi Guys New joiner to the forums. Thanks for having me. I have been working my way through my sons 1986 MK2 Scirocco 1.8 electrical problems and I've finally reached the horn issue. No horn when the steering buttons are pressed. It's fitted with a dual horn. I have disconnected the left horn as you look under the bonnet and put 12v across the terminals and it works. I haven't managed to get to the right side yet as I need better access. I have checked the earth return and the 12v line to the left horn connector and both are sound. The thing I've noticed is relay 53 does not click when the steering buttons are pressed. Can I just pop any multi purpose VW 53 relay in to test it or does it have to be a legacy item? Many thanks Paul and Dawson
Hopefull rubjonny will be along with his knowledge and wisdom. Until then, have you pulled the horn pad off of the steering wheel? From that you can disconnect the spade and short it down to earth. Worth a try
Hi Cressa, I haven't had the horn pad off properly yet. I just did the 9v battery test on relay 53 and the Relay is good. It clicks over and I have continuity. I guess the next step would be power at the back of the fuse board to relay 53?
Something I did find with old VW fuses was either her weren't sitting right or had blown and I couldn't see properly. I now always take them out and test for continuity. Might just be my age though. Still worth pulling the horn pad as you can check it is connected correctly as this finishes the circuit
Tried an earth check under the steering wheel pad and the resistance is all over the place. I’m thinking the steering wheel perhaps isn’t seated correctly on the brass ring.
Try a flying lead back to the batter. Help rule things out. Rubjonny will have the circuit wiring diagram for you too I'm sure
So I took the steering wheel off and the brass ring is clean as is the brass spring lever that it connects to. I think the earth from the wheel down is suspect. If I probe for earth under the steering pad I get high resistance. where does the earth go from the steering wheel? I did connect one horn to the battery and that works. tomorrow I can spend all day on the car in the light. A wiring diagram from Rubjonny would be great.
Here is the wiring diagram from the Bentley for a mk2 golf. Can't be much difference. Pressing the horn button obviously earths the relay coil, which then energizes the circuit live side for the horn.
No idea with that one. I can click on it and the enlarge..... I'm no techno, I would have to get my glasses on
The way I'm reading the diagrams correctly is I should have a permanent live sat at the fuse box on socket 86 of the relay 53 which is waiting for a ground from the button being pressed. This then operates the relay and allows power to the horns. So I'm going to check the fusebox tomorrow.
53 is a normal type relay, have you tried bridging the two slots in the fusebox to test? On Allie's Green mk2, ce1 box, he horn stopped, was the single type and didn't have relay original, so I fitted it in, can't remember exactly but for some reason I think 2 fuses then came into the equation, might be worth checking them all, or even for damp tarnished contact. https://www.clubgti.com/forums/index.php?threads/fusebox-faq.219775/ Invaluable resources on here, and recommend paid membership, it keeps us alive and the knowledge available.
Morning dodgy I haven't bridged the fuse box yet. I did test the relay with a 9v battery and multimeter and it's good. The two fuses 16, 18 are fine. I'm sure we have 12v at the horn end when we tested the other day. I still think the fault lies switch side to fusebox. The fuse 53 connectors on the fusebox did look a little green so I will try and clean them if I can get in there. I will try again tomorrow when the boy is back.
Have you tried the horn on the battery directly, my mk2 horn failed on its mot test, even though worked in the morning. Damp in older electric bits can be a nightmare, along with the brass tarnishing on contacts both of the component and the fusebox itself. Could even be the relay, internal contacts burn up, some get so hot under load that they desoldered the pins, my old caddy van used to cut out as the 109 relay was a common problem for this.
I tried one of the horns direct from the battery and it works. I’m sure I have 12v to the horn too. The connections at the fuse box are my next port of call as they looked a bit green when I took the relay out. The relay works out of the car. I’m going to test for 12v and earth at the fuse box tomorrow. I’ll post my findings.
What happens when you touch the two wires together that are coming out your steering wheel, with ignition on? And also check the little brass contact tab that you can see with the wheel off is not bent so far back that it doesn't make contact. If you run a jumper wire from battery negative to earth trigger the relay does the horn sound? if so then it sounds like something is not switching the earth between the wheel and the fusebox. could also bypass the relay to rule it out, or try another 53 relay
