Alarm Siren issue

[petehall347]

https://www.microchip.com/en-us/product/pic12c508a

[slybunda]

fantastic. any ideas on how the read the code from this chip? can it be done with an arduino uno?

[CapLeaker]

removed the sticker of the small chip and its got some markings on it:

12C508A
04/P01V
0113

maybe if i can find a datasheet for this it may give schematic info of whats supposed to be connected to it and how?

Its a PIC microcontroller.

[lti]

That's a microcontroller, so it all depends on the program.

https://www.microchip.com/en-us/product/pic12c508a

Damn, I missed page 2.

[redwire]

OP cross-posted galore, it's ridiculous:
https://forum.allaboutcircuits.com/t...n-issue.198936
https://forums.overclockers.co.uk/th...ai606.18984085
https://bobistheoilguy.com/forums/th...n-issue.378880
https://www.eevblog.com/forum/chat/c...rm-siren-issue

Must be a relative of treez Sound the siren I need attention.
Is OP fixing it, but says they've bought a new one.
Why bother with the MCU - if it's damaged, you ain't reading any code out of it, and even then the code protection bit is likely set.

Can you fix this siren? Consensus: NO the board is cooked too badly.
Why post all over the Internet?

[petehall347]

scrapyards are full of these things .
personally i wouldn't bother and drive without it . its only there to make noise that nobody bothers about apart from complain .
i did once remove one from a car because it kept going off whilst driving . had to stuff a rag hard against it
to make it quieter it then remove it from the car when it was sounding then threw it in a bucket of water to shut it up .

[slybunda]

OP cross-posted galore, it's ridiculous:
https://forum.allaboutcircuits.com/t...n-issue.198936
https://forums.overclockers.co.uk/th...ai606.18984085
https://bobistheoilguy.com/forums/th...n-issue.378880
https://www.eevblog.com/forum/chat/c...rm-siren-issue

Must be a relative of treez Sound the siren I need attention.
Is OP fixing it, but says they've bought a new one.
Why bother with the MCU - if it's damaged, you ain't reading any code out of it, and even then the code protection bit is likely set.

Can you fix this siren? Consensus: NO the board is cooked too badly.
Why post all over the Internet?

i dont have a replacement siren for this one. someone is sending me a different type of siren which i may be able to use for parts.
iv worked out the part of this siren thats used for charging the battery, looked like they used zener diodes for a constant voltage charging system, the big diode on the board is to prevent the battery in the siren back feeding to the alarm control box. this should be fixable once i get to look at another siren that uses a similar type of setup to get an idea of whats going where.
no harm in posting in different places since people on different forums dont always go on all the other forums too.

also you missed one more place where its been posted, can you find it?

[slybunda]

scrapyards are full of these things .
personally i wouldn't bother and drive without it . its only there to make noise that nobody bothers about apart from complain .
i did once remove one from a car because it kept going off whilst driving . had to stuff a rag hard against it
to make it quieter it then remove it from the car when it was sounding then threw it in a bucket of water to shut it up .

iv tried 2 of the largest scrapyards in my city and nothing available from them. 10 years ago this would have been very easy to nab but now not even ebay etc has any. dont think anyone needs and aftermarket alarm and immobiliser since all cars came standard with it after year 2000 or so..

[slybunda]

Managed to get a replacement siren from a newer model alarm. Its not perfect but works well enough