Horn not working

39buss · June 2, 2016

My horn isn't working. I did unplug the horns when I left the car unused with the Battery disconnected because the horns sounded on reconnecting the Battery and I didn't want to disturb the neighbours or wreck me lugs. I been using the car for a couple of months now and remembered the horns were still unplugged and connected them today and discovered they weren't working. The 10amp fuse under the bonnet is ok but swapped it with another but no joy. Unplugged and re-plugged the horn leads but still nowt. Just wondered what the lead is for going into the item next to the horn. Bonnet alarm maybe?? Any ideas please

The-Acre · June 2, 2016

It may not be the same thing but my horn stopped working (on my previous LS430) so it failed the mot. After many attempts and swearing it simply turned out to be a bad earth where the steering column has a nylon knuckle joint. I took the plastic cover off around the steering column and simply joined the two sides with a piece of wire. There is a post somewhere under horn not working.

steve2006 · June 2, 2016

Is it a single horn on the LS430?

There should also be a horn relay possibly located in the engine compartment fusebox, if you have a multimeter remove the horn plug and set to DC Volts connect the leads to the 2 wires in the plug, get someone to press the horn pad and see if the Battery voltage appears.

The-Acre · June 2, 2016

29 minutes ago, steve2006 said:

Is it a single horn on the LS430?

There should also be a horn relay possibly located in the engine compartment fusebox, if you have a multimeter remove the horn plug and set to DC Volts connect the leads to the 2 wires in the plug, get someone to press the horn pad and see if the battery voltage appears.

It's a double horn.

steve2006 · June 2, 2016

Arr wasn't sure with the 430 so we can safe assume that both horns haven't failed at the same time, when I get a few minutes I'll take a look at the wiring diagram and come back to you.

39buss · June 4, 2016

Mysteriously, I've now got a very weak intermitent horn which sounds like there's only one horn working and it only works if I press the left side of the horn push. What colour is the earth wire and I'll look for a relay on Monday. I was fiddling around under the dash to remove the defunct tele steering column motor earlier this year so may have disturbed something. Thanks for the suggestions.

The-Acre · June 4, 2016

I don't know what color the earth is but I know my problem was intermittent as well, it also work sometimes when I turned the steering hard without the engine running.

39buss · July 31, 2016

MOT's due in Sept. so took both horns off and connected direct to the Battery and they're both working so the problem is in the wiring or horn push or as The-Acre says, a dodgy earth on the steering column which I'll look at this week. If no luck my regular garage will sort it along with a new MOT as I don't like the idea of taking the wheel off and risking the air bag.

MLW · July 31, 2016

Had a VW Polo many years ago that failed an MOT because of the horn. I was annoyed as I had not tested it. The garage cleaned up all the terminals and it worked fine. The fact that some 'electricity' is getting through, might suggest iffy connections.
I would clean and check every connection. You could take a lead directly from the Battery to one horn and see if it works.

Don't forget, these horns are right out in the front where the wet, and salt, and grime are. They do corrode but one does not notice as one uses the horn (in the UK) or infrequently.

The-Acre · August 1, 2016

9 hours ago, 39buss said:

MOT's due in Sept. so took both horns off and connected direct to the battery and they're both working so the problem is in the wiring or horn push or as The-Acre says, a dodgy earth on the steering column which I'll look at this week. If no luck my regular garage will sort it along with a new MOT as I don't like the idea of taking the wheel off and risking the air bag.

It'll take you 30 seconds to see if the problem is the same as I had, just get yourself any piece of single wire. I touched one end on a door hinge bolt and the other on various parts of the metal supporting the steering motors, you don't need to take the steering wheel off just to experiment with it, it's worth a try. Maybe get someone to hold the horn pad down while you do it (or use your head as I did!)

39buss · August 1, 2016

MLW. I did that to test the horns and they're working.

The-Acre. As can be seen in the photo the earth is good, clean and tight. I looked at this this morning before I looked on here so again a good tip but I've had enough. It'll go for its MOT and my trusted garage will sort it. Thanks to all. Jim

39buss · August 1, 2016

After reading this I couldn't help me self and for the sake of two screws took the top cowling off the column, cleaned the paint off a door bolt, did the 30 second test, used me loaf on the horn push and YIPPEE working. Loosened a bolt on the column and screw on the bodywork. which were easyish to get at, wound the wire round the washers and tightened up and job done. What a Forum. Thanks for all the suggestions.

The-Acre · August 1, 2016

56 minutes ago, 39buss said:

After reading this I couldn't help me self and for the sake of two screws took the top cowling off the column, cleaned the paint off a door bolt, did the 30 second test, used me loaf on the horn push and YIPPEE working. Loosened a bolt on the column and screw on the bodywork. which were easy to get at, wound the wire round the washers and tightened up and job done. What a Forum. Thanks for all the suggestions.

Well done you! And I guess it may point to a problem that will come up again as we've both had it, at least now we know the solution. Happy honking!!

GrahamG · August 2, 2016

Jim, please explain what is 'the 30 second test' you did?

39buss · August 2, 2016

GrahamG just look at the thread 4 postings above this one, above the photograph, from yesterday by The-Acre. He describes it in detail.

Verbout · August 2, 2016

11 hours ago, GrahamG said:

Jim, please explain what is 'the 30 second test' you did?

Come on Graham, pay attention. :)

GrahamG · August 2, 2016

I knew when writing my question somebody would reprimand me but I could not see the significance of 30 seconds. Had an image of Phil holding his head on the horn press and counting to 30.

Just keep the noise down while I doze off again.....zzzz