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Technical ‘Alarm fault’ fault finding

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Technical ‘Alarm fault’ fault finding

puntoboii

puntoboii

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Hey all been searching for why the stilo kept coming up with alarm fault everytime i started the car. Checked all earths they are fine but came across this in the siren! :(. My question is how easy are replacement sirens to source? In talks with shop4parts and left him to do some research to try and find me one because i can’t seem to find one. Other question is could this be the likelihood of the alarm fault on the dashboard? Thank you for your time. [emoji16][emoji106] IMG_0094.JPGIMG_0095.JPG
 
Yes.... that will be the problem. Water gets into the casing and destroys the PCB tracks, electrolytic capacitors and supply pin connections to the PCB.

I've had 2 like that; one I managed to repair, the other (below) was beyond repair.

Second hand ones are not easy to source. It took me about a year to find a clean working one. I suspect car breakers don't bother removing the wiper arms and scuttle panel when dismantling a car, so don't know the siren is there.

Is there a part number on a white label at the back of the siren?
.
 

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I'm a electronics engineer and we have a techncal term for a board in that condition - buggered.
It now just water ingress, most have rechargable battery packs and even if they don't actually leak the fumes are corrosive and trapped in the case. At least it does not appear to be coded like some of the later ones. Check for a breaker on ebay who is listing a Stilo, they will remove parts to order.

Robrt G8RPI.
 
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Davren said:
Yes.... that will be the problem. Water gets into the casing and destroys the PCB tracks, electrolytic capacitors and supply pin connections to the PCB.

I've had 2 like that; one I managed to repair, the other (below) was beyond repair.

Second hand ones are not easy to source. It took me about a year to find a clean working one. I suspect car breakers don't bother removing the wiper arms and scuttle panel when dismantling a car, so don't know the siren is there.

Is there a part number on a white label at the back of the siren?
.
Click to expand...



There’s only this label on the back of it dude. Shop4parts sourced a new one from Italy for £120! Told them ill have a nosey at eBay first before going that route. IMG_0097.JPG
 
g8rpi said:
I'm a electronics engineer and we have a techncal term for a board in that condition - buggered.
It now just water ingress, most have rechargable battery packs and even if they don't actually leak the fumes are corrosive and trapped in the case. At least it does not appear to be coded like some of the later ones. Check for a breaker on ebay who is listing a Stilo, they will remove parts to order.

Robrt G8RPI.
Click to expand...



I’ve messaged a couple of breakers on eBay just awaiting on replies. Anything i can do if i do manage to source a new one? Like a layer of sealant or a rubber o ring around the opening to stop water getting in?
 
There's already a thick rubber seal between the two halves of the casing. The siren is sealed in potting compound at the front, and the connector plug at the back has a rubber seal in it. I've no idea where the water get into it.

The part number (46762746) on yours is the same as both of mine. It's changed several times, so other part numbers you could search for are: 60816161, 46527912 and 1378325080.

Be careful getting one from a breakers. As well as the original factory fitted alarm siren, there was also a META accessory kit available from Fiat. The two sirens look the same and are fitted in the same place but are likely to have different firmware. Only way I can think of to tell the difference, is that the original factory fitted one will have the volumetric and anti-tilt cancelling switches, and volumetric sensors in the front interior light panel. The META kit doesn't have them. This also helps at the breakers. If the car doesn't have the switches and sensors in the interior light panel, then there's no point in them, or you, removing the wiper arms and scuttle panel. ;)
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Davren said:
There's already a thick rubber seal between the two halves of the casing. The siren is sealed in potting compound at the front, and the connector plug at the back has a rubber seal in it. I've no idea where the water get into it.

The part number (46762746) on yours is the same as both of mine. It's changed several times, so other part numbers you could search for are: 60816161, 46527912 and 1378325080.

Be careful getting one from a breakers. As well as the original factory fitted alarm siren, there was also a META accessory kit available from Fiat. The two sirens look the same and are fitted in the same place but are likely to have different firmware. Only way I can think of to tell the difference, is that the original factory fitted one will have the volumetric and anti-tilt cancelling switches, and volumetric sensors in the front interior light panel. The META kit doesn't have them. This also helps at the breakers. If the car doesn't have the switches and sensors in the interior light panel, then there's no point in them, or you, removing the wiper arms and scuttle panel. ;)
.
Click to expand...



I’m gonna have to do some digging as my local breakers don’t have any stilo’s in (well the one i mainly go to doesn’t) stupid place to mount it if you ask me. Who needs to take wiper arms and scuttle of i managed to get my 10mm in behind the scuttle (lots of swearing) and got the little bugger out without removing them. Probably a lot easier with them removed but i was lazy ??
 
Davren said:
There's already a thick rubber seal between the two halves of the casing. The siren is sealed in potting compound at the front, and the connector plug at the back has a rubber seal in it. I've no idea where the water get into it.

The part number (46762746) on yours is the same as both of mine. It's changed several times, so other part numbers you could search for are: 60816161, 46527912 and 1378325080.

<SNIP>


.
Click to expand...


Do these sirens have batteries in them? this could explain the corrosion more than water ingress. Its very hard to get a totally watertight seal on this type of unit. Heating and cooling over the years can draw enough moisture in to cause issues. Rather than trying to seal it up I'd put a small silica gel desiccant pack in it, but only if it does not have batteries. You sometimes get the packs in the packaging of electronics or shoes. Make sure it says silica gel and rejuvenate it by putting it in and electric oven oven at 80-100 degrees for an hour or so (or buy new ones on ebay).
If it has batteries the best thing to do is vent it, drill a hole in the case, glue a small diameter hose (screen washer size) into it and run it downhill to somewhere dry in the engine bay or into the cabin.


Robert G8RPI
 
g8rpi said:
Do these sirens have batteries in them?
Click to expand...

Yes.... there's a 6 cell rechargeable battery pack in it. The pack in my faulty siren didn't have any corrosion on it, and the location of the battery pack within the large rubber block seal, is not conducive with the damaged area of the PCB.

I think the car has to have an alarm with battery backup to make it Thatcham Category 1 compliant. Without the alarm the Stilo is Category 2.

When getting online insurance quotes, I always select the 'Thatcham Category 1' option rather than the 'Factory Fitted Alarm' option. Seems to make the premium between £20 and £30 less. Only once did an insurance company query it. I sent them a copy of the letter from Fiat and they accepted it. ;)
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Just the vapours from Ni-Cad or Ni-MH and normal atmospheric humidity are enough to cause corrosion without any visible battery leakage. I've seen expensive (more than cost of a car) RF test equipment destroyed by the fumes from a small memory back-up battery. With battery packs it can even be drawn down the wire by capillary and electrolytic action Google black wire corrosion.


Robert G8RPI.
 
I had a thought whilst busy at work earlier..... If the OP is getting annoyed with the constant alarm warning on the dash - would unplugging it and running a proxy alignment not shut it up.

Albeit if you left it like that you'd have to declare to insurance you've no longer got an alarm fitted.
 
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