I recently had my 2004 XC at a dealer for a visit to Vida for erratic window operation (see post below). I also had a failure to open on the sunroof. The dealer found codes uem-0004 and 0005 and test of the siren module determined the module to be failed. Estimate to R and R was $460. I try to do as much as possible myself. Where is the module, what does it look like, is a used module a good idea, and what are the pitfalls of me doing the R and R? Will it need to go back to the dealer (vida again?) to set operation? Any advice greatly appreciated.
Bill

Edit:
I did a search online and did find some additional info. The R and R that I found was for a S80 which had the module in the right front fender well which is accessed after removing the inner fender. Is the 2004 XC70 the same?

 

I'm having the same problem, '03 xc - alarm would go off at random, I pulled fuse 38 and then the sunroof would stop working, now when I replace the fuse it keeps blowing - after googling/etc. I found the alarm siren and sunroof are on the same circuit -

Apparently, with age, the battery inside the siren module begins to leak acid onto the circuit board in the siren, which is causing the fuse to blow. wonderful

I found this DIY - looking at the comments of this page it seems to be the same for xc's

http://www.matthewsvolvosite.com/for...p?f=11&t=17479

I called a local indy shop, they quoted $150 labor to replace (plus parts), part at the dealer is $241, I found one online for 185 (w/shipping) - seems straight forward, I'll attempt myself

http://volvowholesaleparts.com/partl...subcat2=159752

good luck, if you replace, just be sure to do the lock/unlock with key three times as it resets everything, don't think there's a need to have to go to dealer