V40 Electrical Mysteriousness!

volvosc · Post by **volvosc** » 18 Jan 2011, 11:57

OK, so just got the transmission replaced on our 2000 V40 (ouch, $$$) and all is well and good until a week later all of a sudden, all at once, the radio has no power, the clock and the dash computer (MPG, miles to 0, etc...) reset to zero every time the car is turned off and our door ajar light is always on (though the doors are all closed tight). Anyone know what might be up or where I should start to figure out the problem? This car has also not had working shift indicator light, fan dial light and temp dial light since we bought it from the original owners a few years back. Any thoughts? Thanks.

Post by **jimmy57** » 18 Jan 2011, 12:50

Check the fuses. IF it has a blown fuse look in owner's book and see what else is powered by that fuse. The label on fusebox is often not as complete a listing as what is found in owner's manual.
Something on the fuse may be something related to transmission R&R or it is a random problem with no relationship to the performed work.

volvosc · Post by **volvosc** » 19 Jan 2011, 10:35

We started with the fuses, but they all check out OK. What next do you think?

Post by **jimmy57** » 19 Jan 2011, 11:05

Fuses were checked in the car and under the hood?
IF they are all known to be good then it gets uglier. Central electrical module starts being suspect. Then it is time to get codes scanned by someone who can read the whole car and not just OBD-II fuel system info.

volvosc · Post by **volvosc** » 20 Jan 2011, 11:13

Yeah, checked the fuses again last night for good measure and they all look good (but how am I supposed to get at those three in the engine compartment with the yellow box/clamp wrapped around them?) Is the scanning or reading you mentioned a way to figure out the fault without tearing things apart? I've got a recommendation to start replacing switches (specifically the dash computer dial) in a sort of process of elimination strategy, but it seems to me that could get messy and expensive very quickly.

Post by **jimmy57** » 20 Jan 2011, 11:18

Yes, getting the car checked out by reading the fault codes in all the systems is better way to spend money towards a fix.
You may have to go to a dealer or to an independent shop that specializes in Volvos. A lot of shops can read the power train but few can read all systems in the car.

Post by **yuckuJackD** » 21 Jan 2011, 03:00

volvosc wrote:but how am I supposed to get at those three in the engine compartment with the yellow box/clamp wrapped around them?

You could check them using a multimeter. One more thing: sometimes a fuse looks like it's OK visualy, but when you check it with the multimeter you realise it's not.
What I'm trying to say is that I'm 80% sure your problem comes from a 10A fuse in the engine compartment fuses box, but I don't remember which exactly. I had a same/similar problem and that was it - the fuse which visualy looks OK, but actualy was... hmm.. not blown, but broken and make contact from time to time in combination of bad contact between the fuse and the fuse-box.
I said I don't remember thich exactly the fuse was. But what I remember is:
1. The fuse was 10A (red)
2. The fuse was in the mentioned yellow box
3. The fuse was for: interrior lights, radio memory and some other things don't remember...
Hope this will help you.

p.s.If you need I could take a photo of mine fusebox and post it here. Just ask.
Good luck.

p.s.2 Replace that fuse, clean the plug (WD-40 is good idea for clening) and you'll be fine.
The main reason for reseting the dash computer is that while unlocking the car the electric mechanisum consumes alot of power and when the contact between the fuse and the fuse-coupling is bad the dash stayes without power for a part ot the second and "forget" the millage, the clock and so on...
Good luck

p.s.3 There is one more possible reason: low baterry or bad connection with the baterry.
Good luck

p.s.4(Last p.s. I promice, otherwhise I'll write a new post). The clock! What time it says? 00:00? If so it means that the dash board is just resetted in less than a minute. This way you'll be sure when exactly the problem occur and what you did that that moment is the cause. If unlocking ot opening the door - it's the fuse. If starting the car - bad connection with the baterry or low baterry.
Tell me what happend AND WHEN.
Good luck

volvosc · Post by **volvosc** » 21 Jan 2011, 13:44

Interesting. OK, it could be that 10A fuse. I couldn't really check or replace it because I was thwarted by that yellow box/clamp that has those three engine compartment fuses so securely locked up. How do I get the box off or the fuses out? Thanks again for the insights.

Post by **jimmy57** » 21 Jan 2011, 14:03

The fuses still pull out of that holder like they do from other positions. That holder was a storage thing prior to new car delivery. The car will run with those items not working and the battery drain with key off is far lower while in transit or storage. The yellow gizmo can be discarded and fuses inserted directly for that matter.

volvosc · Post by **volvosc** » 22 Jan 2011, 22:05

I tugged, pulled, torqued and even gently pried, but that little yellow box ain't coming out and the fuses held in it aren't either (pretty near ruined my little fuse pulling tool trying). Its a sort of lock-box it seems. No one I call around town is familiar with it, but the owner's manual has a little dotted line around those particular three fuses showing where the box is (but nothing about how to get at the fuses it holds). Thoughts?