The horn on my 1992 240 stopped working. Mechanic told me horn needed replacing and was going to charge a fortune so I thought I would do it myself. Seems easy enough, bought a new horn, 12 volts, 2 wires but nothing happened. If I connect one of the poles to earth (car frame) the horn sounds continuously as soon as ignition is switched on. Fuse is fine, wipers are working normally. Does the 240 need a special horn or am I doing something wrong?

 

When I had my 240 I changed the horns for non Volvo units with no problem, so I don't think a special horn is required.

The intriguing part of your question is that the horn sounds continuously when you connect to earth and switch on the ignition. It should still need you to push the horn button on the steering wheel to get it to work, and it should stop when you let go of the horn button. This would lead me to suspect that the original horn may not have been the problem.

Have you tried reconnecting the original horn using the earth you now have? If the original works like the new one it could indicate that you had a bad earth. It would also mean a fault in the horn button on the steering wheel, probably making continuous contact.

 

Thanks for the reply! I exchanged the horn for another one, "universal", same result. However I've left it on and after pounding the steering wheel for a bit noticed it worked fine if I pushed on a certain area. obviously problem lies in steering wheel but am reluctant to take off the cover as that's where the airbag is located.

 

Check the Ground in the steering wheel and the Horn buttons