Alarm system service required?
 

2008 Volvo S40 with roughly 189,480 miles. Yesterday on 6/9, my wife was driving home in the rain and about three different times the message "alarm system service required" would quickly come up on the dashboard but then disappear afterwards; she didn't notice any other problems. It didn't happen as she drove to work today on 6/10 and it also wasn't raining. Our local mechanic had looked over our battery cables the previous day on 6/8 and determined they were fine for a separate issue, but not sure if this would even be connected? Just wanted to bring that up in case. Also, our battery was just replaced in 01/21 if it helps. Please keep in mind I'm not a car guy so I'm not savvy in that sense to fix things on my own.

Thanks for any help!

could be the siren battery...

https://blog.fcpeuro.com/how-to-fix-...p2-s60-v70-s80

You stated rain, and the first thing comes to mind is water maybe in the electronic control box. I had this issue with all the rain we recently had in the Houston area.

Hey guys, just wanted to bump and update this. The message didn't come up again since that one time on 6/9. But it did just happen again yesterday on 6/16 as I was driving it at 189,877 miles. It happened just like my wife described it, quickly came on with the same message for like half a second and then quickly disappeared. It wasn't raining though this time. It didn't come back after that and it didn't come up as my wife drove to work this morning on 6/17.

I'm so confused on how to proceed with it, lol. Why is the message literally only coming for a split second and then disappearing? If it needs to be addressed with a shop, does the shop have to use VIDA to look into this? Because I have one mechanic who doesn't use VIDA, instead they use Autologic and Autel. But then I have another mechanic who does use VIDA.

Bumping and updating this. The message hadn't come up since my last post saying it did on 6/16. But it did again this morning on 6/25 at 190,406 miles while my wife drove to work. Same display as always, a quick split second appearance and then quickly went away. I called one of my local shops that I use last week about it. He mentioned it's a common issue and does probably mean it could be the alarm/siren module? He said to replace it would be roughly $600-$700 or another option that most people do and they recommend for cheaper is to instead delete the software and in essence get rid of the alarm system all together I believe? He said that would only be roughly $300-$400 and basically eliminates the cancer so to speak. This is what they said most customers do and just means you won't have an alarm system but everything else will work as normal. I believe he said by leaving this message and not fixing the problem through one of these two options, it could potentially drain your car battery and/or cause issues with your doors, etc.?

Anyone's thoughts on this? Also, can I get a reply on these questions below from my previous post? Thanks!

"Why is the message literally only coming for a split second and then disappearing? If it needs to be addressed with a shop, does the shop have to use VIDA to look into this? Because I have one mechanic who doesn't use VIDA, instead they use Autologic and Autel. But then I have another mechanic who does use VIDA."

Bump thanks

I dont think the S40 2004 on has a separate battery for the alarm , so as its not on all the time its probably a faulty earth somewhere , do you live near the coast ? corrosion is a big thing there , probably needs the contacts cleaned , best to remove and clean , but you can spray some Q40 or similar over the connectors and see

It's not a 2004, it's a 2008. Please see my last post too in regards to what my local shop recommended.

I meant the models from 2004 onwards

Thanks but again I'm not car savvy and can't do those things you mentioned doing. And from most others and my local shop, it seems like it is going to be the alarm/siren module that needs replacing or software deleted. Can anyone else reply to my questions/comments from my last post on 6-25 regarding what the shop said? Thanks.

Still no replies? Would really hope someone would answer some of my questions/comments from my post on 6/25...thanks.

Just another update...so it happened again for the 4th time in total now I believe, yesterday on 7/3/21 when my wife was driving home from work at roughly 190,760 miles. This time it came up about 4 times which is probably the most in one drive. Sometimes a split second, other times a little longer for a few seconds but then always disappearing like normal. Just as a reminder, the last time the message came on before this was 6/25. Our local shop said they could get us in sometime soon but I kind of have a dilemma...Hoping to travel to see family within the next weekend or so but I'm not sure if the car is safe with this issue to travel on. Not sure if I should fix it beforehand or rent a car instead? The family lives 3 hours away...so 6 hours total. Thoughts on this and my post from 6/25 with what the shop said would be appreciated.

FWIW, I would think that it's likely that the only "failure" you'd get from your current situation would be the alarm system wouldn't work, which shouldn't prevent a road trip. There are probably some ties between the alarm and the immobilizer, but I'd expect that nothing about the alarm system "feeds" the immobilizer (which would potentially prevent the car starting if it did).

Please take that FWIW - I am not 100.000% familiar with Volvo alarm systems (never having to work on either of my Volvo wagons' alarm systems).

Also, taking in a car with a problem that intermittent can be an exercise in futility - "if it ain't broke, they can't fix it", basically. They could spend hours on it and know no more than you do right now.

Well if it was the immobilizer the car will not start , once disabled its good to go , the alarm is different as it resets with power loss , so I would still check connections .
The car is fine to drive dont be too concerned about the warning , You can also disable the alarm but every time you restart it will reactivate. By the way is the remote working properly?
The alarm runs of the car battery and there is no other power supply for it but is part of the central locking so if you park in a garage etc where its safe dont lock it , locking for short period like at a shop etc will be fine , also disable auto locking when driving this may stop the warning messages

Thanks a lot, I appreciate your guy's feedback. Yes the key fobs are working just fine and so is the locking of the car. No alarms going off either at any random time. We don't have a sunroof either. Unfortunately my shop said this issue could drain the car battery while it lingers and other issues with doors, etc. so that's where my dilemma lies with whether I should drive the car on this trip before fixing it. Any other thoughts on the issue itself and what he mentioned about most people choosing the option of just removing the software rather than replacing the alarm/siren module? Anyone heard of that type of fix for this issue? He said it would just mean we wouldn't have an alarm system anymore but a cheaper fix by a couple hundred dollars.

I am not sure what your car is worth in your country , but here with around 300k on (Km) its not a lot so I assume even less where you live , the alarm was option on these cars (no alarm needed in Sweden ?) so leave it I dont see how it can drain the battery if you use it regularly , if you park it locked for a week or so perhaps after a month or so . I would certainly not fix this problem unless your car is in fantastic condition and you have really looked after it and you like it.
I personally think you being ripped off in both cases , but then I do not know the labour rates in your country ,
Have you tried driving it with the auto lock turned off ? Its under car setting in the menu

Thank you guys again for your feedback.

My shop took it in and confirmed after diagnostics that there was a trouble code of CEM-DD1B meaning signal missing between the siren control module and the central electrical module. My two options were to replace the the siren control module for around $600-700 or go with what they recommended which was to install the necessary software and just delete the alarm siren module function from the vehicle which I did for around $400. So now we have no alarm system but he said this is what most customers did and what he recommended given the age, etc.

So the problem is resolved now with the error message.