Ok, so you have tried the quick fix and that does "bugger-all". Now it's time to get a bit more serious. These instructions below are very likely to cure a problem which is caused predominately because of a window switch contact becoming non-functional over time.

You need: a soldering iron, perhaps a little solder, torx screwdriver bits to unscrew 2 different size torx bolts.
And a modicum of ability with simple electrical bits.

Executive summary... what you will be doing:

1. Disconnect Battery. Take the lower centre console out.
2. Open up the window switch cluster.
3. Remove wiring and metal conductive plates from the back of the switches.
4. take out switches, "recondition" and swap them around.
5. Reinstall everything in reverse order!

What happens to these switches? Over time, the significant current that the DPDT switches have to control causes the terminals of these switches to wear down and also become coated with oxidised metal and carbon. This stops current getting through! The terminals that control the "up" direction of the window are particularly likely to go first, and this may lead to a very inconvenient situation (depending on environmental factors such as climate, temperature, or suspicious dudes hanging around your car).

If you have a Haynes manual, it offers basic instructions & pics on how to
Remove the centre console.
This is basically done by

• removing the two torx screws that hold the ashtray in place, (near the top on either side)
• then the two that hold the front part of the console (that holds the lighter) in place,

(close to the tranny lever and facing towards the front of the car, hard to see at first)
• then the two on the metal cross bar that holds the front of the console down to the body (see fig 1)
• then the two under the plastic plate in the centre console rear compartment (see fig. 2 below), (cover just clips out with gentle blade screwdriver encouragement) and then
• pulling out the piece of plastic that resides under the handbrake lever (fig. 3). Grab from near the handbrake and GENTLY lift.

figure 2

figure 3
 
 

WARNING Before touching wiring, you need to disconnect the negative lead of the battery.
Failure to do this might see you cooking something, and costing you $$$$. Don't miss out on this step!
(Also make sure that you have the radio code to get it going again.)

...and then you can unplug the terminals that lead to the main body of the centre console
(On mine, one was black, and one was grey)
...and then pull out the whole centre console.

It has to move forward to clear the handbrake, and then should lift right out of the way.

Get the console to a soft space that won't scratch it, and rest it upside down.

Find the spot underneath that corresponds to the window switches. (see the top pic or fig. 4 if you're still drunk.)

All of the plastic bits of the switch box come apart, as detailed below.

Be very gentle as you go along, as you want these plastic bits to not be broken so that
they do their job when you reassemble everything! Some bits are particularly delicate,
such as the small black plastic sections that hold each individual white DPDT switch
block in place (explained further below).

figure 4
The two cables unplug and the top part of the switch box will come off.

figure 5
This is the top of the switch box detached and upside down.
Note the way that the plastic teeth hang down and grab the rest of the switch box.

You could probably do this two ways; the lazier (or more clever?) method would be to get all of the
individual switch blocks out of the switch box without taking off all of the wiring connections.
Afraid I can't help you with that method: it is quite delicate in there and I don't know that you could
get it all out without maiming something. Having said that, this is how I did it:

Take note of all of the connections such as

• the specific colours of wires, & which ones feed each switch or terminal on the metal plate
• the two metal plates, and which one sits below the other
• which wires or terminals attach to each plate.
• Basically you need to write down all of these connections.

(It might be a good idea not to rely on this pic & "schematic" (I use the term loosely), or make sure all your connections are the same as mine before doing so.)

figure 7
Here's a rough schematic of how mine was wired. (Photoshop art by Picasso aka OzBrick)

Then comes the fun of removing all wiring to the switch assembly. I just hit each connection with
the soldering iron and the wires popped out quite effortlessly. Didn't even need desolder.

Once you have done this, you can do the same for the wires that join to the metal plates.

figure 8
The two plates. They are only slightly different:
see the terminal/hole on the left hand side one's left arm near the middle.

Then for the connections from the metal plates to the individual switch blocks.

figure 9
40% of the job has been suffered by this point...

Now the switch blocks are on their own and they can be pulled out and apart.

Take each switch out one by one.

figure 10

figure 11
The shot is too dark but the red line is where, on either side, there is a black plastic piece that holds down the white switch block.

A delicate black piece of plastic holds the white blocks on the left and right, as viewed from the angle seen in the shots (10-11) above.
Gently prise the plastic away from the block with a flat blade screwdriver (about 6-7mm across would be good).
Start with the switch that has probably gone first, the drivers side front window.
(bottom right window switch in fig. 9/10)

Separate the black top part -the "user interface" that is the rocker button itself,
from the base part. It just grabs on at it's axis or hinge point; pull gently outwards and then apart.

Button at left, main body of switch at right. Look down to see loose copper strips and ball bearings still in place.

Switch assembly complete except for top plastic rocker button.

There are two free ball bearings inside, and two copper V shaped rocker pieces. don't lose 'em.

(You can also see a green LED that illuminates.
You don't need to do anything with that but stay away, unless the light has
gone in which case you will want to replace it.)

Be as gentle as you can to assess the configuration of the switch.
This will help you understand how they work, if you don't already know, and how they go back together.

Now assess which two points out of four points on the switch are most carbon'ed up and worn.
There is a pattern to the wear as you can see above. Held with the LED at the top, the
top left and bottom right terminals wear most heavily. They are likely the ones that carry
the up-window current.

If you have no easy source for spare parts to replace the whole DPDT switch, then you are like me and have
to make do with what we have. So this method is hopefully a close to full reconditioning for them:
this of course depends on how badly worn they actually are.

the block stands naked. Assess worn terminals.

The good news is, every bit of every switch is the same, except for the inconsequential bit of the top drivers
switch that says "auto" for auto full unwind of the window. So you can mix and match. And fortunately we don't have
to worry about any special wiring for this driver's switch, it's all taken care of as long as we reinstall the same way we took apart.

I took both switch blocks from the rear (much less used) windows and moved them and their copper components to the front.
Both of the (most worn out) front switches went to the rear.

On each switch, swap over the two points that are most heavily worn and carbon'ed up, for the sides that are less so, by inverting and crossing over the copper V plates that rest under the ball bearings.

And of course clean up all terminals manually with a bit of alcohol/methylated spirits and, if you see it as necessary (it probably is),
perhaps a light touch of wet and dry sandpaper on the terminals to freshen them up.

That's all you do; reinstallation is the reverse of the take-apart, and if you have done all the correct swapping then the switches should
last you for almost as long as they did the first time round, before you have to go reconditioning again. I say this because you will note that the rear windows usually won't get so much wear (unless you have feral kiddies) and the down-window-current terminals will certainly be less worn than the up ones.

Make sure that you put the button top marked "auto" back onto the new driver's window switch that came from the rear: don't put it back onto the old and more worn block that you have moved to the rear!

--OzBrick.

OzBrick,

I don’t know what possessed you to document the reconditioning of the Volvo 850 master window switch, but you did it.

I had the dreaded “window goes down, but won’t go up” problem in my ‘94 850.  It’s December here and coooooold and snowy.  We had this
problem once before, 3 years ago, and the dealer charged us $USD240 to replace the switch.  This time I wanted to find a cheaper route. Your
page showed me the way. Now it works great.  You just saved me $240 !!

Thanks.
 

I scraped off the points with a razor, and cleaned them with isopropanol.  Swapped the V-rockers just like you suggested.  I lost one of the bearings
(!!) but replaced it with one of my daughter’s tiny plastic beads.  It feels the same now that it is all back together.

Before I saw your page I had pulled the switch box (this bit:  ) without removing the entire center
console.  I used a putty knife, a wide blade so as not to damage the plastic casing with a narrow-bladed screwdriver.  Just pried it right out.  And I
had the soldering iron all heated up, but then I figured, hey! Why not just take apart the switches while they are still wired?  So that’s what I did.  I had
to bend the plates  a bit to do this.  But they went right back when I re-assembled it all.   It saved
me a few steps.

Anyway, thanks!

Dino

(Pittsburgh)

Thanks for the info. What possessed me? I know it's a little bit of an arcane mod to put up, but whenever I do something to the ol' 850 now, it goes up there. I do it because I am happy to help people like you! And I believe that what goes around comes around!

cheers
Michael/OzBrick.com