Car alarm siren issue

[slybunda]

car alarm siren seems to have gone nuts looks like these pics explains it:

dunno where to begin on this. its a toad ai606 so not gonna be easy to find replacement.

[mendip_discovery]

Personally, I would reach out to https://www.toadalarm.com/ and see if they might offer help/support.

Some of these places can be quite good at making an offer to repair/replace parts for not a lot.

[PlainName]

its a toad

My, how restrained you are!

 

[slybunda]

Will contact toad and see what they say. I thought these came with a lifetime warranty

[slybunda]

more pics here

[mendip_discovery]

Ouch, leaky battery. I wonder if they created a short that killed the mosfet (or what ever they are).

Well and truly fooked.

[slybunda]

I think those 3 mosfet looking things are transistors of some sort i wonder if they are like amplifiers for the they have a part number of tip32c. Brand may be just the F letter on it not sure what brand it is and there is also a 122 number on it.
Anyone know what it is and suitable replacement? Rs components in the uk is best for me since i can drive down and collect.

The resistors, am i right in thinking a resistor with single black band is 0 ohm?

[tom66]

You can replace TIP32C with ... TIP32C.  It's a very common transistor made by many manufacturers.  Beware that resistor next to the transistor also looks damaged to me and the value is not obvious.

The 'F' is probably Fairchild.

[slybunda]

excellent i guess this one may work: https://uk.rs-online.com/web/p/bipolar-transistors/4859777?gb=s  ?

some resistors do look damaged im going to desolder stuff today hopefully the bottom side of the resistor that touches the pcb doesnt have burn marks so that i can see the bands on it.

[slybunda]

more pics after desoldering stuff,

[slybunda]

some trace damage too looks like a single layer board so not sure now.

[tom66]

The Jxxx numbering next to the suspect damaged resistors suggests they are jumpers.

I'd check the transistors next door were not thermally damaged, that board looks like it got toasty!

[slybunda]

zener diode is bust, not sure where to go with that, the 2 resistors although black seem to both be giving a resistance of 102 ohm and 101.5 ohm, so they could be 100 ohm resistors. all resistors marked with a Jxx measure at 0 ohms so they just jumpers i guess.

[slybunda]

The Jxxx numbering next to the suspect damaged resistors suggests they are jumpers.

I'd check the transistors next door were not thermally damaged, that board looks like it got toasty!

The other 2 transistors seem to test ok without removing them.

[slybunda]

anyone know if the zener diode thats broken is part of the circuit thats responsible for charging the internal 7.2v battery? if so i can probably leave that part out of the circuit since i dont intend to put a battery back in it.
the other side where the traces have gone is the tricky part but its not micro soldering and has space to work around so may be able to just use wires to connect parts back up?

[slybunda]

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?

[tom66]

That's a PIC12C508A microcontroller.  It's not going to be replaceable because it will have firmware embedded into it.  If you suspect it is fried, the whole device is scrap, unfortunately.

[coromonadalix]

That's a PIC12C508A microcontroller.  It's not going to be replaceable because it will have firmware embedded into it.  If you suspect it is fried, the whole device is scrap, unfortunately.

unless  by some miracle they forgot to lock the mcu from being read ...     no luck to recover the firmware

[tom66]

That's a PIC12C508A microcontroller.  It's not going to be replaceable because it will have firmware embedded into it.  If you suspect it is fried, the whole device is scrap, unfortunately.

unless  by some miracle they forgot to lock the mcu from being read ...     no luck to recover the firmware

Yes, if they forgot to lock it, but even if it is unlocked if the MCU has been killed by something failing in the circuit board, it is unlikely to be able to connect to the programmer anyway.

[slybunda]

what can i use to try and read the code from the chip? would it work with an arduino uno or one of those ch340 things?
also i dont think it is dead because the siren still worked as in if i hold the panic button on the key fob the alarm goes off making its usual sounds.

[Zero999]

what can i use to try and read the code from the chip? would it work with an arduino uno or one of those ch340 things?
also i dont think it is dead because the siren still worked as in if i hold the panic button on the key fob the alarm goes off making its usual sounds.

I've got one of these. It works, but getting the software to play with Windows 10 isn't straightforward.
https://www.ebay.co.uk/itm/285338791568?chn=ps&_ul=GB&_trkparms=ispr%3D1&amdata=enc%3A1jw06wFvKTdykemi3JplpQQ35&norover=1&mkevt=1&mkrid=710-134428-41853-0&mkcid=2&mkscid=101&itemid=285338791568&targetid=1647205088280&device=c&mktype=pla&googleloc=9046050&poi=&campaignid=19688986533&mkgroupid=146538074536&rlsatarget=pla-1647205088280&abcId=9307891&merchantid=138357265&gclid=CjwKCAiAlJKuBhAdEiwAnZb7laoIozbhaBS6r-13ZqKm4EaIish6QtMlL8o1UtriS_71ozLqCSyeyBoCnmgQAvD_BwE

[slybunda]

can it be run from a windows 7 or xp machine in a vm?

[Zero999]

can it be run from a windows 7 or xp machine in a vm?

Probably. The software is quite old and designed for Windows XP I think. I had trouble setting up the USB port. If I remember rightly, it uses one of those dodgy USB to serial/parallel chips.

[mendip_discovery]

So did Toad Alarm not offer to help?

[slybunda]

Toad alarms said they can sell me a replacement siren which is at a ripoff price. No warranty since alarm comes with 1 year warranty and iv had it for over 20 years.

[Zero999]

Toad alarms said they can sell me a replacement siren which is at a ripoff price. No warranty since alarm comes with 1 year warranty and iv had it for over 20 years.

What's so special about this siren? Have you looked into replacing it with a third party one? It's likely that's the most economical solution.

[NiHaoMike]

I would fit a pair of SPDT relays to the existing car horns, wired so that by default, the horns operate as usual and activating the relay activates each horn individually. Then use a classic 2 transistor oscillator to alternately operate the relays when the alarm is sounding to give a high/low cycling rather than the usual car horn sound that often gets ignored.

[mendip_discovery]

Toad alarms said they can sell me a replacement siren which is at a ripoff price. No warranty since alarm comes with 1 year warranty and iv had it for over 20 years.

What's so special about this siren? Have you looked into replacing it with a third party one? It's likely that's the most economical solution.

Surprised they weren't more amicable. Good luck with the repair, if all else fails you could DIY or get a better unit.

[slybunda]

I would fit a pair of SPDT relays to the existing car horns, wired so that by default, the horns operate as usual and activating the relay activates each horn individually. Then use a classic 2 transistor oscillator to alternately operate the relays when the alarm is sounding to give a high/low cycling rather than the usual car horn sound that often gets ignored.

The alarm doesnt use the car horn it uses its own speaker

[AVGresponding]

I think NiHaoMike is suggesting you use the alarm output to switch the car horn via an oscillator/relays.

This of course will only work if the alarm active output still works as it should.

If you need replacement sirens I have any number of old fire alarm sounders, a sample of which you could have for the cost of postage. There are some fully potted piezo types which would probably work best.