W202 - How to test car alarm?

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Unsure. I never bothered with it !

Sent from my iPhone using MBClub UK
 
Didn't win that new one on eBay, called my local dealer they confirmed the part number is A2198203226 and is 83.50 + VAT.
 
The attached images show the location of the siren and removal / installation details. Wish I'd known that yesterday I could have took it off whilst I had the wheels off the car.

I've just taken apart and looked inside the off side front wing for this siren to take it off and its not there! Might be under the near side wing? Or in the engine bay maybe?

Thanks
 
Passenger side (nearside) take off front wheel arch liner. Behind Yellow arrow.


Dec
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Dec

Thanks found it, was a pig to remove, had to remove the entire siren bracket but its off the car now. Cant get the siren off the bracket though, its a weird bolt looks like an alan key type but has a pin in the middle of it, Ive not got any tool to fit the bolt. Might have to grind it off.
 
Get a hammer and whack the centre pin sideways with a chisel or drill bit to break the pin off, you can then use an allan key to undo the bolt.
Taking the siren bracket off first is the easiest way of changing/removing the siren.

Dec
 
Thanks, my mechanic is going to lend me some, but now I've seen them on eBay I might as well buy some.

Cheers
 
I've got the siren apart now my new tool arrived, its certainly the circuit board that is shot and all corroded, looks beyond repair. However the battery looks to be quite clean and doesn't look like its leaked etc. But the battery is dead no volts on the multi-meter.

I contacted Scorpion Auto Alarms they manufacturered the units and they now say no spare parts are available and its now obsolete. It appears in the past you could buy the circuit board or even the whole siren unit from Scorpion cheaper than MB etc but not anymore.

Looks like I will have to bite the bullet and go to the merc dealer for the part.

For the record the part number of the original siren I've taken off is 220 820 28 26 other markings on it were:

PBT-FR
ELSER S.P.A (aka Scorpion)
Made in Italy (Probably why it doesn't work lol)

Cheers
 
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I recall that alright, someone was saying, quite a while back, that you could buy the siren from Scorpion at nearly halve the price of the dealer.

My siren batteries appeared good too, just the corrosion of components on the PCB seemed to be the cause of its demise. Maybe it’s the circuit board that kills the batteries and not the batteries that kill the circuit board.

Dec
 

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Maybe.. The nice chap I am currently talking too at Scorpion says:

"Yes its a common issue they leaked water around the wiring connection to the siren"

I've contacted Bosch Automotive UK as they manufacture the new siren part. Worth asking if they can put me in touch with a Bosch dealer, never know might be possible to get the new siren a bit cheaper that way? Can't harm in asking anyway's.
 
If you hit standing water you could let water into the siren, I moved my siren for that reason, from its original location to just above the suspension on passenger side, it’s a cleaner location , dry, more secure and has a more stable temperature environment.

Dec
 
If you hit standing water you could let water into the siren, I moved my siren for that reason, from its original location to just above the suspension on passenger side, it’s a cleaner location , dry, more secure and has a more stable temperature environment.

Dec

Top tip! Might look at that, was the cable long enough for it to be moved to the higher position?
 
I recall that alright, someone was saying, quite a while back, that you could buy the siren from Scorpion at nearly halve the price of the dealer.

My siren batteries appeared good too, just the corrosion of components on the PCB seemed to be the cause of its demise. Maybe it’s the circuit board that kills the batteries and not the batteries that kill the circuit board.

Dec

Dec

I see you added some photos!

My circuit board was a lot worse than that!
 
I forgot to mention earlier, that guy from Scorpion I was talking too, also said this with regard to the new Bosch siren

"Trust me it’s made under license and is Merc only it’s sad I know but it’s the way they operate and the big issue is its coded so only that siren will work with the alarm to be honest I wouldn’t bother do without the siren least its immobilised"

Nice of them to code it so you can only use their OEM siren!
 
That’s the way it is alright, the siren is the alarm system, and the brains of it all, everything else is just door/bonnet sensors/boot and tilt/motion sensors, so when you buy a new siren you are really getting a new alarm system.


Top tip! Might look at that, was the cable long enough for it to be moved to the higher position?

No need to cut or shorten any wires.
Unwrap or unwind the electrical insulation from the 3 wires that go to the siren.
This wiring loom goes from the 3 siren plug wires to 5 wires after you have undraped about 2 feet of insulating tape.
Continue unwrapping the electrical tape until you have enough of the siren wires to reach the new siren location.
Put the electrical tape back on to all wires, you will probably need some extra new tape..
The other 2 wires go to the bonnet switch (2 wires to the bonnet switch and 3 to the siren plug)

I would put up a picture but I’m all out of my quota of pixels.

Dec
 
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Hello, do you know if there is a way to test my alarm on a new C-class 2015 ?

I do not have the PANIC button on the electronic key.

Thanks.
 
Don’t know that car but you could try locking with the remote, after 1 minute unlocks the car with the metal emergency key blade, as soon as you open the door the alarm should sound.

Unlocking the car with the remote should disarm the alarm.

If you have Keyless Go you need to keep that away from the car while you unlock with the metal key blade.

Dec
 

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