horn goes off randomly while driving

[Mehmood1994]

Hi all new to the forum, I have a w205 c200 in manual, bought it as a cat s repaired, bodywork looked good and took the plunge thinking it'll be okay...
A week later i notice the horn was not working... Checked the 115 fuse in the engine bay and it was blown so replaced it! Horn fixed!

A few days later in driving around town and a horn goes off... My horn! But not the same horn that I sorted.

I know it's not the steering horn as i took out the fuse that I had put it and I had the issue again!

Really not sure what to do it's embarrassing!
I turn off the parking sensors and the car seems fine and have not heard them go off yet so might be an issue with that?

Also keep getting the collision prevention assist inoperative message...

Any help would be very much appreciated!

 

[markjay]

I suppose you mean the alarm sounder? As opposed to the car horn?

The alarm sounder has built-in rechargeable Ni-Cd batteries, when they become old, the sounder starts behaving as if it has a mind of its own. A new sounder is needed, though if you are good with the soldering iron you could pray open the old sounder and replace the batteries. But of course the car being a Cat-D it is not impossible that when the car was being repaired someone messed-up the alarm system wiring.

If it's the horn... then I would think you have an issue with wire chafing or perhaps worn contact ring in the steering wheel - did the steering wheel come-off for the repair?

 

[Mehmood1994]

I believe it is the alarm sounder, do you know if and where the fuse is? Could I just remove that and be done with it? The cars always parked in a locked garage or private car park, thanks

 

[219]

I believe it is the alarm sounder, do you know if and where the fuse is? Could I just remove that and be done with it? The cars always parked in a locked garage or private car park, thanks

The easiest way would be to deliberately set off the alarm and follow the sound to find the offending unit . On many , there will be a multi pin connector plugging into the sounder , which you can remove , it will then go dead when the internal batteries run down .

Alternatively , you might have a key to disarm the alarm ? Often you will find a key switch somewhere ( often in the glovebox ) where you can simply turn the alarm system off .

Good luck .

 

[markjay]

You may not be concerned about theft, but you should really inform your insurer if you are deliberately disabling an anti-theft device on the car?

 

[markjay]

On some of my previous cars the alarm sounder was located inside the front wing, accessible by removing the wheel arch internal lining. I am not sure where it is on your car (and I also don't remember on which side the sounder was fitted...).

 

[daveenty]

To be honest I'd be more concerned about the state of the wiring which is enabling the car to do all this.

It definitely needs a dose of looking at and I'd be back to the supplier with it to ensure it's not going to burst into flames...

 

[Mehmood1994]

To be honest I'd be more concerned about the state of the wiring which is enabling the car to do all this.

It definitely needs a dose of looking at and I'd be back to the supplier with it to ensure it's not going to burst into flames...

By looking online it seems to be a fairly common issue?

 

[Mehmood1994]

The easiest way would be to deliberately set off the alarm and follow the sound to find the offending unit . On many , there will be a multi pin connector plugging into the sounder , which you can remove , it will then go dead when the internal batteries run down .

Alternatively , you might have a key to disarm the alarm ? Often you will find a key switch somewhere ( often in the glovebox ) where you can simply turn the alarm system off .

Good luck .

Found the fuse for it, believe it's 202 in the driver's side fuse box and have just taken it out till I get a proper chance to look at it. Will update if that is the correct fuse

 

[219]

You may not be concerned about theft, but you should really inform your insurer if you are deliberately disabling an anti-theft device on the car?

If it has an on/off switch , as many do , then you’re under no obligation to have it turned on .

The insurers only ask if one is fitted .

 

[markjay]

If it has an on/off switch , as many do , then you’re under no obligation to have it turned on .

The insurers only ask if one is fitted .

Agreed, but removing a fuse is a different matter...

 

[219]

Agreed, but removing a fuse is a different matter...

If he wanted to be ‘fly’ , he could deliberately blow the fuse then put it back in .

In the event of a claim , he could say he had no idea the alarm wasn’t working

 

[markjay]

If he wanted to be ‘fly’ , he could deliberately blow the fuse then put it back in .

In the event of a claim , he could say he had no idea the alarm wasn’t working

... and ask KillerHERTZ to delete all his posts on here?

 

[Mehmood1994]

If he wanted to be ‘fly’ , he could deliberately blow the fuse then put it back in .

In the event of a claim , he could say he had no idea the alarm wasn’t working

I do like that idea insurance companies have tried to play around with a claim I had previously and I think they're one of the biggest scams around

 

[Mehmood1994]

... and ask KillerHERTZ to delete all his posts on here?

Let's face it insurance companies don't even care to inspect anymore, they're happy with a 50/50 fault and then charge the person the next few years stupid amounts!

 

[markjay]

Let's face it insurance companies don't even care to inspect anymore, they're happy with a 50/50 fault and then charge the person the next few years stupid amounts!

In case of a minor damage-only collision, this is quite often the case, sadly.

But when the insurer is faced with a substantial payout, they will allocate the resources to ensure that they are indeed obliged to pay. But will they scan the claimant's social media activity...? Probably not (though the police and CPS have been known to do this in cases of serious injury resulting from an RTA).

 

[Deleted member 113659]

‘Horn goes off randomly whist driving’.

Those bl00dy speed bumps eh???

 

[Mr. B]

On a lighter note my front door bell goes off randomly when no one is there.
Im convinced it’s my father who’s back to haunt me from the other side.

 

[whitenemesis]

On a lighter note my front door bell goes off randomly when no one is there.
Im convinced it’s my father who’s back to haunt me from the other side.

Ours did this, found out a neighbour had the same door bell and we were on the same wireless channel. A quick adjustment to select the next channel sorted it....

 

[Mr. B]

Ours did this, found out a neighbour had the same door bell and we were on the same wireless channel. A quick adjustment to select the next channel sorted it....

I would have to have some fun and games with my neighbour if that was the root cause.