General Technical Questions and Answers last answered over 1 year ago.
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I had a problem a while ago with my horn only working when the steering wheel was in certain positions.
I eventually tracked it down to the short earth wire that goes from the back of the horn push to a little slot in the aluminium steering wheel boss. The spring connector and ally slot were both corroded. I gave them a good clean up with emery cloth and it's been fine ever since.
I noticed that if I had the voltmeter attached to the fuse box the horn would work, regardless of whether the voltmeter was on or off. I guessed that there was a short behind the fuse box which was disconnected if I pushed on the fuse.
I think I was correct, as the horn worked when I fiddled with the fuse, although the strange whirring sound which came from the engine compartment was a little worrying.
I am assuming that the whirring sound is the reason why the van wont even turn over now. So I have a horn that works when I push the fuse in the right direction, pity the van doesn't start.