2004 s80 trunk lock (2.5t awd)

[Kaba]

Hello everyone,

First post here, long time searcher. I have a 2004 s80 2.5T awd that I purchased used and I am experiencing a strange problem with my trunk.

The only way to open it is with my key fob (press trunk button 2x on fob, walk to rear of car, press release button, vola!), I cannot get it to open otherwise using the central locking or regular key in the door.

There is an alarm warning when I turn on the car (presumably my batteries have leaked/gone dead and killed the module) however I am happy to ignore that issue for now (the sunroof still works), and I don't think the issues are related.

Using the key in the door 1x unlocks driver door, 2x all doors. Trunk locked.

Pressing the lock button on the door from the inside locks/unlocks all doors. Trunk locked.

I assume any unlock goes through the central locking, and the fact it works from the fob means the actuator works (I can hear it work when I use the fob only), the button on the trunk lid works too (since I have to press it to open the lid once I double press the fob). The sensor knows when I leave the trunk open (for example I unlock the trunk with the fob and then start the car without opening the lid and I get a warning issue).

Does anyone have any suggestions on how I can narrow this down?

With covid I've been doing a lot of curbside pick up, it's a real annoyance in winter to turn the car off and take the key out to unlock it.

Thank you!

[ndphotonl]

The alarm warning is the dreaded battery leak issue yes. I have that as well on my 2001.

Hmm strange issue though, I dont know if you have VIDA, but you can see the separate modules in the car with their respective error messages. I cant remember if the (central) locking is also one of them though

[Kaba]

I very much appreciate the reply thank you!

I need to do research on VIDA, I do have a Bluetooth Obd2 adapter and I'm hoping I can use that via my laptop and some VIDA software - again more investigating is due on my end.

One other symptom I've noticed, when I lock the doors/unlock the doors/unlock the trunk with the fob, other than hearing the locks physically click into place there are no audio or visual signs that anything happened (no horn beep or lights flash etc.).