Instrument Panel and Control Panels went dark
 

Could someone please tell me where the circuit board is located?

no idea which circuit board he's talking about, the only one involved in what you're describing is the back of the instrument panel.

re: wiring diagrams, the only reasonably accurate ones are the volvo 'greenbooks' specific for you year car.

if someone messed with the wiring, my first order would be to put it all back the way its supposed to be, or document what changes were made, perhaps by drawing over copies of the greenbook pages with the modifications.

Regarding the gas gauge showing full all the time. My bet would be that when the previous owner installed the new in-tank pump, he installed an aftermarket in-tank sending unit. These aftermarket sending units are know to come with incorrect wiring resulting in the fuel guage wired to the in-tank pump and vice-versa. The resulting symptoms are the gas gauge showing full all the time and the in-tank pump not working. Take a look at the wiring as described in the link below - most specifically, the wiring to the little black connector in the trunk. If it is backwards, that explains the gas gauge issue.

In the Tank - 240 Volvo Tank Pump and Sender

Regarding the circuit board, the only one I can think of is on the back of the instrument cluster as Pierce noted. There is a plastic fuse on the cluster that looks like a small flexible plastic circuit board. If that fuse blows, all power to the cluster is out and would give the sympoms you describe. To get to the fuse, you have to remove the cluster. The fuse is the back above the speedometer and is attached by screws on each end. There will be obvious burn marks if this fuse is blown.

Thanks for the feedback.

And yes someone also mentioned the after market sending unit. I will ask the guy. We email back and forth.

And as for the panel being DARK. It's not anymore. It came back the way it was a couple of days ago. So I dunno.

I have an app't with the Volvo guy on Wed. I am going to call him and tell the news and see what he says.

Thanks y'all!

As far as the gas gauge goes it looks like you got it right.

Here is the response I got from the guy who sold me the Volvo:

Hey, this could be a breakthrough - it does have an aftermarket fuel pump, that a friend helped me with sometime back. But the only problem with this theory is that I got a normal reading for a little while (like a day.) But perhaps this is still the issue - which makes it sound super easy to fix...

Thanks! :)

Just replacing the pump generally doesn't cause the gas guage issue you describe. It is the aftermarket gas gauge sending units that come wired improperly. Check out the link I placed in my earlier post. It describes the wiring as it pertains the pump and sending unit. You don't even need to pull the sending unit out to check it. It is at the black plastic connector in the trunk that has the wires reversed.

Ok. Thanks for that.

Could you please show me specifically which pic on the page of the link you sent are what I need to check. Where is the 'black plastic connector'?

And mine is a wagon. Is this the same fix. Cuz there is no trunk in a wagon.

on a wagon, its under the floor panels just behind the back seat. fold the back seats down flat, lift up those hinged panels and you'll see a couple 3 screws/bolts. remove those and the access plate is a black oval thing with a few screws, the pump/sender access is under that

My Volvo has a third jump seat and one long back seat. Here are the pics:

imgur: the simple image sharer

imgur: the simple image sharer

that back seat doesn't fold down? it should be under the panel just behind the back seat, NOT the 3rd seat/spare tire compartment.

sorry - got some sort of brain cloud here. I just don't get what you're saying.

And yeah the back seat folds down.

I'm looking at the two pics I posted here.

So, you mean I fold the back seat down - actually forward - and it's under the panel behind the back seat. Right in back of the back seat is the 3rd seat. I don't understand where or how to get to the panel.

When you have the third seat out it is under the third seat.

oh crap, I was describing where it was on a 7/9 wagon. yeah, on a 2 wag, its under the third seat, right behind the main back seat.

I believe you have to remove the 3rd seat. Underneath there is a panel that you can access the top of the in-tank sending unit.

In the link In the Tank - 240 Volvo Tank Pump and Sender, look at the 9th image from the top. It lists the different wires that run to the sending unit and in-tank pump. Check the colors of the wires against those on your car. The plastic connector is near the center of the photo (it has the dental pick inserted).

It's fixed!
 

and thank you all.

The link with the pics helped a lot. My oldest son fixed in a jiffy and it's
wonderful cuz I ran out of gas today and finally tracked him down.

I am excited to know I don't have to guess anymore.

You all are great for helping.

Thanks

Now to fix the lights on the instrument panel so I can see the dash at night.