Dash lights go out.

Go to your fuses, find the fuse and pull it, clean it, and replace it. I recently had an issue similar to yours, but with the jake brake. While I was driving my brother pulled the fuse, cleaned it, and reinserted it. Problem solved... thankfully as some monster down grades were approaching!!

First choice for solving these kind of intermittent electrical issues is to check the fuse and make sure it is seated properly and is clean. If that doesn't solve it then replace the fuse. If that doesn't solve it then drink a beer and call 911.

 

Its a volvo. Hit the dash and see if it shakes something back together to get lights.

 

a possible source of trouble is the dash dimmer light switch.mine kept doing the same thing and when i replaced the headlight switch . problem solved. i've heard a lot of people grip about volvo electrics and i wonder if the root of all that is because a lot of times the switches control several functions. when you pull almost any switch , you will see several , and i mean several wires plugged into the back. anyway hope this helps. johnny

 

Volvo dashlights are controlled with LCM. LCM reads dimmer voltage from potentiometer and converts it to CAN data for Instrument claster and LCM controlls dashlight brightness with PWM

 

This ! Pablo got it right.
I had same problem Tuesday morning after delivering at Chrysler in Toronto, all my lights got messed up, signal ,brakes not working and the headlights were on without turning the switch on.Was the first day of the safety blitz, # #&$&&#it.The light diagnose on dash was showing 5-6 faults. I drove slowly with flashing on to Volvo in Mississauga and they reset the light control module, located under the fuse panel behind the stereo. I didn't know how to do it myself, the technician just unplugged and plugged the power to light control module, and problem fixed.
Pablo, what if you disconnect /connect the cables from batteries ,would this work also for LCM reset?