Service Issues: Siren Modules, has anyone got a schematic

[joshp]

Seems like the siren modules for Volvos like my Volvo v70 2001 model are becoming even harder to find these days and the prices are ridiculous

I have spent today getting the siren Module out of my car opening it up in attempt to change the battery but unfortunately all the battery acid has done a number on the circuit board and the board is fried!

I was just wondering whether anyone has been able to retrieve a circuit schematic for the siren module. My main interest is the LSC441309CFN chip. What does it do? what's its inputs and outputs? The rest of the circuit looks relatively easy to get my head around.

Has anyone had a go at reverse engineering this circuit board?

I'm sure with how fast 3d printing is coming along the case could be duplicated.

Would be good to have a oem version of this alarm so we don't have to pay £150 plus for a new alarm.

Let me know what you guys think. Am I being stupid?

[stellamon]

Did the same om my v70 t5, circuit board knackered. Just left it off in the end and kept turning the service message off. It's really no big problem.

[MarvinMitt]

I carry my gear in the car so working alarm is important to me.
However I have found breakers sell them around 40£ so if you find a good one (might need to try a few), just replace the battery and you'll be good.

To me the access is easier through the front by removing the bumper and headlight, it just slides out of the bracket.

[barrybritcher]

Josh - the alarm will still trigger just not the noise so here's what I did:-

Chop in a £40 all in one alarm which just has a 12V sensing wire as the trigger to the passenger indicator - so when the Volvo alarm is triggered and the aftermarket one has been armed it will sound the new siren.

Don't worry it will not sound when you indicate as you wont be driving the the new alarm "armed"

[cjsv70est]

Originally Posted by joshp

Seems like the siren modules for Volvos like my Volvo v70 2001 model are becoming even harder to find these days and the prices are ridiculous

I have spent today getting the siren Module out of my car opening it up in attempt to change the battery but unfortunately all the battery acid has done a number on the circuit board and the board is fried!

I was just wondering whether anyone has been able to retrieve a circuit schematic for the siren module. My main interest is the LSC441309CFN chip. What does it do? what's its inputs and outputs? The rest of the circuit looks relatively easy to get my head around.

Has anyone had a go at reverse engineering this circuit board?

I'm sure with how fast 3d printing is coming along the case could be duplicated.

Would be good to have a oem version of this alarm so we don't have to pay £150 plus for a new alarm.

Let me know what you guys think. Am I being stupid?

I used these if link works eBay item number:162122881395 Bit odf a pain to complete but an easy job

[cjsv70est]

Originally Posted by joshp

Seems like the siren modules for Volvos like my Volvo v70 2001 model are becoming even harder to find these days and the prices are ridiculous

I have spent today getting the siren Module out of my car opening it up in attempt to change the battery but unfortunately all the battery acid has done a number on the circuit board and the board is fried!

I was just wondering whether anyone has been able to retrieve a circuit schematic for the siren module. My main interest is the LSC441309CFN chip. What does it do? what's its inputs and outputs? The rest of the circuit looks relatively easy to get my head around.

Has anyone had a go at reverse engineering this circuit board?

I'm sure with how fast 3d printing is coming along the case could be duplicated.

Would be good to have a oem version of this alarm so we don't have to pay £150 plus for a new alarm.

Let me know what you guys think. Am I being stupid?

eBay item number:162122881395 I used this firm, easy but time consuming

[cjsv70est]

Originally Posted by cjsv70est

I used these if link works eBay item number:162122881395 Bit odf a pain to complete but an easy job

Complete alarms are available on ebay

[GreenBrick]

Originally Posted by barrybritcher

Josh - the alarm will still trigger just not the noise so here's what I did:-

Chop in a £40 all in one alarm which just has a 12V sensing wire as the trigger to the passenger indicator - so when the Volvo alarm is triggered and the aftermarket one has been armed it will sound the new siren.

Don't worry it will not sound when you indicate as you wont be driving the the new alarm "armed"

Sounds like a good idea, what arms the after-market alarm?

[barrybritcher]

You'll have to have another key fob unfortunately. So lock your car as normal. Then use the new alarm fob to arm.

[GreenBrick]

Originally Posted by barrybritcher

You'll have to have another key fob unfortunately. So lock your car as normal. Then use the new alarm fob to arm.

I have 4 cars, 3 of which have faulty sirens units (V70 being one of them)...
The only one that works (the Mazda 2) simply uses the car's horn instead. Go figure!
Is this all so that the alarm will still sound if the battery is disconnected?

I was wondering about making a "generic" arduino based alarm unit to replace at least on of the above faulty ones. Knowing what gets communicated between the car and the siren module would be very useful for each of my faulty cars. I doubt it will be just a simple on off signal, as that would be too easy!