Volkswagen Golf GTE - Help! Car Horn won't shut up - Neil Byrne

Hi all, new to the forum so apologies if this one is covered in a separate thread please feel free to redirect me

I have a 2017 (67 plate) GTE and 4 times in the past month the car horn sounds constantly for over 10 seconds, pauses for a second or two then sounds again constantly when I unlock the car, open the door and/or start the ignition, stop the car, and lock it. Once it starts, it goes off even when the car is locked. It's random, intermittent and of course very annoying...especially to my poor neighbours!

Dealership have tried so far 3 times to identify the fault but can't reproduce it. I have video footage of it happening that I've shared with them and it's with them now but they don't seem to have any idea what the cause might be.

A recent VW tech inspection found a fault that they fixed through their diagnostic systems
Name: HYBRID BATTERY CONTROL
DTC: P0E5E00, Battery charger, internal fault
System Type: -SYSTEM TYPE:47-

Next time they thought it was the horn relay switch so replaced that but next day, the horn sounded again when car was unlocked.

I charge the car every other day mainly using the standard UK 3 pin home charger plug but have also used the rapid chargers at work. There doesn't seem to be any pattern to the issue other than it happens in th emorning, but that;s when I typically first use the car each day to go to work. When it happens the only way to stop it is to remove F15 fuse to disable the car horn.

Anyone else had a similar problem? If so do you have any idea what the cause is?
Thanks

Volkswagen Golf GTE - Help! Car Horn won't shut up - galileo

Is this the 'car alarm' horn sound? Not unusual for some car alarm systems to be set off by breeze blowing through de-mister vents onto the sensor. DIrecting the vents toward the floor leiminates this possibility.

Volkswagen Golf GTE - Help! Car Horn won't shut up - Neil Byrne

Hi, thanks for the reply,

No it isn't the alarm it appears to be just the horn in a single constant sound as though someone was pressing and holding dowen the horn for 10-15 seconds, pausing for a second or two then pressing it again.

When the VW technician first inspected it, we tested triggering the alarm and it's not th esame sound, plus no flashing lights or 'alarm' sound either.

Volkswagen Golf GTE - Help! Car Horn won't shut up - Brit_in_Germany

If they cannot fix it, reject the car.