How to replace your alarm horn

[Mvplayer84]

Do you lock your car via cobra remote or via central locking? It seems that both options activate the alarm?

I lock it with the remote. I have tried the central locking and seems to me that it does the same alarm activation.

[Mvplayer84]

Have no idea about the voltages or how to test the syren outside the car.
What kind of issue do you have? Anyway I think will be easier to just replace it.

When I tried to fix mine by replacing the batteries I've spent money for nothing.

Issue started with alarm going off randomly with siren noise. Now the alarm functions properly but no siren noise even when locking. I want to make sure it is only the siren and not a faulty alarm unit. I am in South Africa and cannot order online from Ebay. Dealer part prices have become expensive after lockdowns here. Second hand siren prices are extortion. I want to make sure especially with no return policy. Hence my voltage question. I cannot find anything on the internet.

[AdeN]

This is same procedure for a 65 plate VW Polo. The alarm siren is under the scuttle vent in centre of windscreen area.
Easy process once you get wiper blade arms off, I used a small puller for this. They are very tight on the spindle.
After removing the rubber seal, The scuttle comes away from the windscreen by easing upwards from one end, it is held in a snap groove along windscreen bottom. Once started it comes off ok. I started moving it with a small screwdriver to ease the end from the groove.
The alarm siren is rivetted on the bulkhead, drill these out & remove the wiring connector by pulling red tab upwards.
Then slide the siren out from the side.
Took me about half an hour to actually do the job after sussing out what to do.

The car seems to run ok without the siren installed.

[Franciswat]

Except for autoscan fault and alarm not working you won't have more issues.

[dunesand]

Hi, did you get you alarm horn sorted?
I am in your region and has the same problem.

[Franciswat]

I replaced the faulty alarm horn (1K0951605C) with a more recent unit (1K0951605F) from eBay.

[djlosmii]

Just want to say thanks for the tutorial!!
I had the same random alarm issue and resolved with a second hand ebay unit using the part number posted here: 1K0951605F
For anyone attempting this - be patient cause it can get tricky!
I had most issues with:
1. Removing wiper arms - I used the cheapest amazon tool and the tip of it fell apart. I somehow managed to still use it and take them off but they really do need a lot of force.
2. Removing the pop rivets. Omg! They used such big size in the factory + it's a stainless steel one so it takes ages to drill out. I managed to brake 1 small drill bit and finally after 30ish minutes took them off with a big drill bit.
Rest is easy.
Seems that I scored a unit made in late 2022/ early 2023 - so hopefully it lasts a while. *50EUR with delivery (there was a promotion on ebay by this parts supplier)





Really silly but inconvenient problem to have - but solvable thanks to people like toy making these tutorials.
Long live the internet, long live the forums - cheers!!

[Franciswat]

I am glad you solved it mate.

[ciclo]

I am glad you solved it mate.

+1

---

Hi, Francesco!
It's great to see you active here... ... warmest regards, and since it's been a while since we last spoke, a very happy 2026!

The same goes for all the users I haven't been in touch with for a while.