Intermittent Horn - Corolla 2006 E11 3Dr Hatch 1.4 Petrol

December 11, 2010

Hi Everyone

I recently joined the forum to look for any info on this problem. (Corolla otherwise works fine for me.)

The horn sometimes fails to work at all. Sometimes the central part of the horn button will work; sometimes it, and the edge areas will work.

The horn itself was replaced by the Toyota dealer under warranty and seemed to work ok for a few months till now - but operation is getting more and more intermittent.

Can anyone please tell me how to investigate the wiring in the steering wheel/ column/ air bag area? I am not clear what platsic panels to remove, or what hidden clips I may break...

Is there a service manual please or forum "how to" on this?

Many thanks, mh.

December 11, 2010

Hi,

How to get to things like that is detailed in the Haynes car manual, but it only shows that central area of the steering wheel as one assembly which houses the horn multi switch, cruise control if fitted and airbag.

It warns you must disconnect the Battery AND allow at least 5 mins for the backup capacitor to dischage before touching anything on the steering unit otherwise you could get seriously injured by the airbag exploding !

I would look at the other parts first, the horn and the horn relay.

Connect a bulb or voltmeter to the horn connectors and press the horn buttons and see it voltage is getting though, also try and listen for the relay clicking in and out as you press the button.

You may have some corroded wiring connectors to the horn or a faulty relay.

If not then the steering wheel horn switches must be suspect, I would then return to Toyota and ask them to fix it properly as they clearly failed to do so under warranty - don't be put off by anything other than YES.

It may be the horn switches are a part of the whole airbag cover assembly and thats why they did not replace it in the first place - an expensive job for them.

If it is the switches but warranty is not an option for some reason, come back to the forum and see if anyone else has replaced the horn switch only or the whole unit.

Don't forget the horn switch is just a simple switch so you could buy any switch and fit it anywhere on the dash area and simply wire it into the horn relay connectors. As long as it satifies the MOT -which I expect simply states you must be able to easily access and operate the horn switch from the drivers seat.

I did a similar thing with my starter / ignistion switch on the old Avensis, fitted a big red push /starter button, looked just like the flash sports car :lol: