Alarm System Service Required - Fix
Discussion
When you get the Alarm System Service Required message on your dash you have a few options:
1. Do nothing/press the Read button. It may go away for a long time or nag you every time you start the car.
2. Go the dealer and pay them to de-code it from the car.
(Note options 1 & 2, you really should remove the sounder module otherwise you are leaving the batteries to corrode and leak nasty acid potentially (although the unit is sealed) onto your car.
3. Remove and replace sounder module with a new unit from Scuderia etc. Current price £122 plus shipping taxes etc, but where’s the fun in that?
4. Replace battery, as long as the existing battery hasn’t leaked its acid over the PCB.
5. Remove and replace with a used unit off the bay etc. Plenty around, it’s a Volvo badged part but used frequently in Land Rover, Range Rover. Part No. YWK500040 for the poverty pack, non-inclination module.
6. Remove and replace with a used unit and replace its battery to give you a longer life.
Assuming you’re going to do something constructive and not bury your head in the sand, you need to get to the module. It’s located in the left rear wheel arch by the fuel filler pipe. You need to remove wheel and remove 4 of the screws holding the liner (2 underneath and 2 rear facing – gives you access to the unit). Removing the liner gives you much better access if you want.
There are 3 captive bolts from which the sounder enclosure hangs from, remove the 3 x 10mm nuts and the enclosure drops down. I recommend that you then loosen the 3 x 10mm nuts that hold the sounder in the enclosure and slide the sounder out (electrical connection still secure) so that you can remove the plug. Doing this gives you access to the tab that you have to lift to remove the plug. If you don’t, you can insert a screwdriver down and push but its awkward. Don’t try and dig it out or mess around with different tools – it won’t come out and you risk damaging the connections.
Once you have the sounder out, time for the real fun.
Open the module, it’s a sealed unit so you need to cut it open. Do not bother with a Dremel etc, whilst they cut the plastic, the plastic gets hot and will re-weld itself back together. Sharp knives will cut the plastic but its tortuous and potentially dangerous to your fingers. Use a hacksaw to cut the joint in one corner then prise the rest apart with a thin wide screwdriver, it will snap apart with a nice cracking sound.
Then cross fingers that the battery hasn’t dumped its load of acid onto the PCB. I only got the warning on the dash on the Friday (its 17 years old and I believe its designed for a 5 year life so not too bad) and removed on the Sunday but the acid had done its job. I had actually never tested the alarm after purchase 1 year ago so I don’t know if it ever worked or not.
|https://thumbsnap.com/6N1FcRrk[/url][url]
|https://thumbsnap.com/mMifjyoe[/url][url]
When shopping for a replacement used unit, helpfully all the sellers will show you the part label and this shows you the manufacture date. My original had a date of March 2006, so go for the most recent unit you can find. I got an October 2007 (from a Range Rover apparently). When it arrived two days later, plugged it in, there was a satisfying blip sound. Turned on ignition, no message on dash. Locked car with remote, unlocked door with key, opened door, cue ear splitting noise, unlock car with remote to turn off alarm – yup, that works!
You can stop here and put it all back together (Option 5) but that’s just queuing you up to do exactly the same in a few months time, so onto Option 6, replace the battery or if you’re fortunate you’re following Option 4 and just replacing the battery. The battery inside comprise 4 x 1.2 volt button NiMH cells connected together to give 4.8 volt 250 mAh.
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You can replace like with like and solder them yourself or replace with a different unit. I opted to get a flat unit with 300 mAH complete with plug from Overlander. I had no idea if the plug would be the same as required but felt that if it didn’t fit I could always cut them off and re-connect.
|https://thumbsnap.com/DakrY96P[/url]
Battery arrived next day. Connector is slightly different but it does fit, however it doesn’t feel as secure. Rather than swap connectors over and induce another possible failure point I just put a blob of glue on the connection to ensure it doesn’t fall out. The battery is a snug fit, I secured it in place with a piece of double sided tape left over from mounting the number plates. Then just put the cut-off lid back in place sealed with some sealant and wrapped with insulating tape for good measure.
Fit back in enclosure and back in car, make sure car is unlocked when plugging it back in otherwise it sets off the alarm and your head will be in close proximity to the aforementioned ear-splitting noise – ask me how I know.
Just a case of testing and tidying up and all is good.
1. Do nothing/press the Read button. It may go away for a long time or nag you every time you start the car.
2. Go the dealer and pay them to de-code it from the car.
(Note options 1 & 2, you really should remove the sounder module otherwise you are leaving the batteries to corrode and leak nasty acid potentially (although the unit is sealed) onto your car.
3. Remove and replace sounder module with a new unit from Scuderia etc. Current price £122 plus shipping taxes etc, but where’s the fun in that?
4. Replace battery, as long as the existing battery hasn’t leaked its acid over the PCB.
5. Remove and replace with a used unit off the bay etc. Plenty around, it’s a Volvo badged part but used frequently in Land Rover, Range Rover. Part No. YWK500040 for the poverty pack, non-inclination module.
6. Remove and replace with a used unit and replace its battery to give you a longer life.
Assuming you’re going to do something constructive and not bury your head in the sand, you need to get to the module. It’s located in the left rear wheel arch by the fuel filler pipe. You need to remove wheel and remove 4 of the screws holding the liner (2 underneath and 2 rear facing – gives you access to the unit). Removing the liner gives you much better access if you want.
There are 3 captive bolts from which the sounder enclosure hangs from, remove the 3 x 10mm nuts and the enclosure drops down. I recommend that you then loosen the 3 x 10mm nuts that hold the sounder in the enclosure and slide the sounder out (electrical connection still secure) so that you can remove the plug. Doing this gives you access to the tab that you have to lift to remove the plug. If you don’t, you can insert a screwdriver down and push but its awkward. Don’t try and dig it out or mess around with different tools – it won’t come out and you risk damaging the connections.
Once you have the sounder out, time for the real fun.
Open the module, it’s a sealed unit so you need to cut it open. Do not bother with a Dremel etc, whilst they cut the plastic, the plastic gets hot and will re-weld itself back together. Sharp knives will cut the plastic but its tortuous and potentially dangerous to your fingers. Use a hacksaw to cut the joint in one corner then prise the rest apart with a thin wide screwdriver, it will snap apart with a nice cracking sound.
Then cross fingers that the battery hasn’t dumped its load of acid onto the PCB. I only got the warning on the dash on the Friday (its 17 years old and I believe its designed for a 5 year life so not too bad) and removed on the Sunday but the acid had done its job. I had actually never tested the alarm after purchase 1 year ago so I don’t know if it ever worked or not.
|https://thumbsnap.com/6N1FcRrk[/url][url]|https://thumbsnap.com/mMifjyoe[/url][url]When shopping for a replacement used unit, helpfully all the sellers will show you the part label and this shows you the manufacture date. My original had a date of March 2006, so go for the most recent unit you can find. I got an October 2007 (from a Range Rover apparently). When it arrived two days later, plugged it in, there was a satisfying blip sound. Turned on ignition, no message on dash. Locked car with remote, unlocked door with key, opened door, cue ear splitting noise, unlock car with remote to turn off alarm – yup, that works!
You can stop here and put it all back together (Option 5) but that’s just queuing you up to do exactly the same in a few months time, so onto Option 6, replace the battery or if you’re fortunate you’re following Option 4 and just replacing the battery. The battery inside comprise 4 x 1.2 volt button NiMH cells connected together to give 4.8 volt 250 mAh.
[url]You can replace like with like and solder them yourself or replace with a different unit. I opted to get a flat unit with 300 mAH complete with plug from Overlander. I had no idea if the plug would be the same as required but felt that if it didn’t fit I could always cut them off and re-connect.
|https://thumbsnap.com/DakrY96P[/url]Battery arrived next day. Connector is slightly different but it does fit, however it doesn’t feel as secure. Rather than swap connectors over and induce another possible failure point I just put a blob of glue on the connection to ensure it doesn’t fall out. The battery is a snug fit, I secured it in place with a piece of double sided tape left over from mounting the number plates. Then just put the cut-off lid back in place sealed with some sealant and wrapped with insulating tape for good measure.
Fit back in enclosure and back in car, make sure car is unlocked when plugging it back in otherwise it sets off the alarm and your head will be in close proximity to the aforementioned ear-splitting noise – ask me how I know.
Just a case of testing and tidying up and all is good.
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