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MG MGB Technical - horn not working

I replaced the dash in my 69 roadster this week and now the horn does not work. As far as I know, there are no wires related to the horn in the dash but, something must have happend. The horns are after-market HELAs installed new about one year ago. When I put a tester on the leads of each horn, I find that they are both hot(juiced). Is this correct? And, they are grounded. I have looked over all the wires and checked the fuses. Help?
Dana

After posting, I went back to the car for another round and found the problem. While installing the new dash, I blew the fuse for the dash board lights,hrn and what ever else. I replaced it with the only spare fuse I had, a Lucas! The fuse worked well enought ot light the dash board lights and send juice to the terminals on the horns but, when I pushed the horn the fuse couldn't take it. When I wrapped Mr Lucas' fuse in tin foil (old trick) the horns sounded fine. I am off to by fuses............
Dana

I have a similar problem with mine. I stripped the cr down and repainteds earlier this year. Now the hjorms dont work. The ysound fine if a hot wire is ran to them. The hot lead for them has juice but they dont seem to want to work.
william fox

William,
I did a search in the archives for 'horn' in the MGB general section and found lots of info. You should go there.
Dana

Horns are hot all the time. You make then toot by completeing the ground at the horn button. If they are hot at the horn, then check if the wire is hot at the button. Most of the time I find that the problem is in the button from lack of a good ground connection.
gerry masterman

If the horns don't work have someone push the button while you check the voltages on the horns. There should be about 12v on the purple and about 0v on the purple/black. Much less than 12v, or no 12v, on the purple indicates a bad connection going back to the fuse block (bottom fuse) or a blown fuse. Much more than 0v on the purple black indicates a bad connection back to the horn button. You have to put the circuit under load to 'see' bad connections with a voltmeter.
Paul Hunt

Add the bumpersticker "horn not working, watch for finger"
.

I like "KEEP HONKING WHILE I RE-LOAD"
Dana

This thread was discussed between 30/12/2001 and 31/12/2001

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