I’ve had my '07 Volvo S40 for almost a year. It has a little over 60K miles on it and is serviced regularly.
Within the last 3 months, I’ve noticed some weird things happening occasionally:
-Trouble starting when cold (I understand this is pretty common with a lot of cars.)
-Headlights & interior lights flickering
-Going over “bumps” in road causing dash display lights to illuminate for a second, radio to shut off, and loud system “BEEP” comes through the speakers (this has happened 3 times total, all on the same day.)
-AC stops cooling periodically
I’ve had the system scanned for the AC issue and it seems that there was a “Pump pressure” message that cleared itself at one point and am guessing the same thing has happened the next few times it’s done this.
I also asked that the battery be checked to see if it needed to be replaced soon. The mechanic said the battery was fine and thinks it’s something wrong with the entire electrical system but couldn’t tell me definitely unless he charged me more money. Figures.
I’m no car expert but I do feel like some of these issues may be related. Does anyone know of any major issues with this year of S40’s? I’ve done some research but can’t find anything consistent.
It sounds to me like you just have a loose or damaged ground wire someplace. At minimum someone should check your main power cables & grounds at both ends (battery, starter, power junction boxes and all grounding points.