Remote key fob no longer opening the doors / disabling the alarm but fob does start the car

SOURCE: S80 electrical issues

Sounds like the rear electronic module is malfunctioning. How do you get the trunk open to find out the light is not working? The REM controls all of the functions you describe in your post. If you can get the trunk open then to this:

Disconnect the positive and negative cables from the battery and touch them together for at least 5 minutes. Don't worry, you will not be doing any damage to the car or yourself. Place the cables back onto the battery and then lock and unlock the car. See what happens. If it works then your rear electronic module (REM) needs a software upgrade at your Volvo dealer, about $120 USD.

Hope this helps.

SOURCE: Alarm haywire, can't override anti-theft system or turn on car

The Alarm on my Mercedes ML320 sounded every night, then it started doing it more often, Showed it to the dealer he says it's the 'Tow Sensor', that needs to be repaced. $700, down the drain. I have already started hating this car, it eats $500-600, every 6 months...

SOURCE: auto door locks 200 volvo S70

You may have a bad master door swith assembly or more fuses out.

SOURCE: remote key will work to open lock but will not

First Check to remote controller battery, on the lock side unless unlock and lock functions share the same battery. Next i would got o my local auto parts store and get a maintence/repair manual for 20.00 dollars from chiltons and see what the book has to say aout your problem. Sorry I cant be of more help.

SOURCE: Keyless Remote Won't Work - But Car Starts

The remote receiver unit is located in the rear view mirror. This may be faulty. Since the car is new (less than a year?) you still may have the factory warranty.

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