Fuse Box removal on an 850

Post by **RyanGLT** » 29 Dec 2010, 11:10

I need to start this topic and get good answers so they can make their way into someone's future searching.

When I first got my 850 Wagon, I tried to remove the Fuse panel to check out the connection on the B+ cable underneath. After trying for the better part of an hour, I gave up and never thought to do it again. Now that I've replaced the positive cable to the starter, I really would like to pull the fuse panel and check out that B+ connection.

The few things I've found online either have no pictures, or they do have pictures, but they're pictures of how to do it on a newer (like 99) S70 or something, where the fuse box is easy to get to and remove, unlike our 850's.

After I had removed the screws when I tried to do it, I could get it to pull up, but it "stopped" at one point and would not go any further.

Does anyone know why that is/what I missed, and does anyone have any PICTURES of the process?

Thanks much,
Ryan

Post by **Ozark Lee** » 30 Dec 2010, 08:09

https://www.matthewsvolvosite.com/forums ... =1&t=35208

...Lee

Post by **RyanGLT** » 30 Dec 2010, 11:26

Lee, as I explained in my post, that is for fixing an S70, which has a completely different main fuse box in a completely different location. While the repair may be similar, the rest of it is not.

VolvoTurbo850 · Post by **VolvoTurbo850** » 30 Dec 2010, 11:59

Your referring to the one you can see just where the windshield wipers are. (you can barely see it on the top right of the picture Lee listed in his post.

Removing that unit requires you to go inside the car on the drivers side and unclip some of the wire harnesses as well as some retaining bolts. Not and easy job in my recollection.

Can you not check the wire using meters or bypass?

Post by **RyanGLT** » 30 Dec 2010, 14:06

I suppose it is possible, but I'm a visual person...I would second guess it unless I saw it with my own eyes.

And really, I think it is a bigger problem on S70's than it is for 850's (850's have plenty of other issues though), and my car seems to be much happier now that I've replaced the Battery to Starter positive cable... but who knows.

Post by **ZionXIX** » 31 Jan 2019, 12:56

So it's been 9 years, has anyone figured put which clips/bolts/cables need to be removed to pull the fuse block out? I'm going to be replacing my dashboard in the future and will be running wiring for a passenger powered seat and will likely need to remove the fuse block to connect everything properly.

greg850r · Post by **greg850r** » 11 Aug 2019, 12:30

This may be too late to do you any good but I installed a passenger power seat in one of mine and the wires were there already. All I had to do was add the missing relay for the passenger seat that was omitted at the factory because the car came with a manual passenger seat.

Post by **ZionXIX** » 11 Aug 2019, 13:42

greg850r wrote: ↑11 Aug 2019, 12:30 This may be too late to do you any good but I installed a passenger power seat in one of mine and the wires were there already. All I had to do was add the missing relay for the passenger seat that was omitted at the factory because the car came with a manual passenger seat.

Mine unfortunately did not. I don't understand how they decided at the factory which ones were pre installed and which were not. You would think the simplest thing to do would be to make a wagon wiring harness and a sedan harness. I pulled up the carpet and follow the cables into the wiring loom just make sure someone hadn't cut then or something. Nope they just don't exist.

msmcrae · Post by **msmcrae** » 05 Dec 2020, 18:10

This may be too late to be useful, but after breaking my relay panel trying to change a relay (really, it just fell apart) I now know more about this process than I ever wanted to. There is an 'L' shaped white plastic panel (the fuse/relay panel) inside a black plastic housing which has a black plastic cover with a liftable piece screwed to it. I would call the black plastic cover, with the black plastic housing, and the white plastic panel inside it the 'fuse box'. The upper part of the white plastic panel holds the fuses, and the relays are plugged into the upper part as well as the lower part. The fuse box fills a hole in the bottom of the cowl which is the mirror image of the hole the cabin air filter goes over on the other side of the cowl. The white plastic fuse/relay panel is actually four pieces, that snapped together in 1996, but at this point they're almost impossible to separate without breaking them. All the 100 or so wires that come into the fuse box from the right side of the engine compartment, the left side of the engine compartment, and up through the hole from under the dash plug into the underside of the fuse/relay panel with connectors that require a special tool (or a tiny screwdriver and lots of patience and cussing) to remove.

You can pull the entire fuse box assembly up from the hole it sits in A FEW INCHES by first removing the wiper arms, then the black plastic cowl top, which requires pulling the two rubber seals (one goes hood hinge to hood hinge, the other around the fuse box), the five T25 screws and two spring hose clamps at its front. Once the screws and clamps are off, you can wiggle the cowl cover out over the wiper assembly shafts and between the hood hinges. This exposes the wiper arm assembly and the four 10mm bolts that hold the fuse box down to the cowl floor. Two 10mm bolts and a couple of wire connectors hold the wiper arm assembly, which should be removed. Then pull the four bolts holding the fuse box down to the cowl floor. Once those bolts are out, and you've loosened the thick wiring harness feeding into the fuse box from its fasteners that hold the harness down to the cowl floor as well as the other part of the harness fastened to the fender wall, you can lift the fuse box A FEW INCHES before you run out of wiring harness slack. The fuse box is actually glued into the cowl floor with a soft rubber seal that will let go if you pull steadily. Start lifting at the side of the fuse box closest to the centerline of the car, and try not to angle it too much -- that is, try to lift it straight up. This is nearly impossible since you can really only pull on two of the four sides, but this white fuse/relay panel is hanging down about a foot below the cowl floor so if you twist the assembly you're just wedging it into the hole.

To really get the fuse box up out of the hole in the floor of the cowl, you'll need to disconnect a lot of stuff under the dash. Pull the steering column cover, the steering wheel, and disconnect all the wires going up the steering column. Disconnect the yellow plastic housing holding the wire bundle from the steering column. Disconnect the wire connector from the brake pedal switch. Disconnect the wire connector from the cruise control switch. There are three huge colored (red, white, and yellow) connectors (each huge one holds about five normal connectors) that plug into a panel under the dash. Each huge connector is locked in place with a purple plastic handle. I pull two of these huge connectors, then I have to pull the panel itself (just loosen two 10 mm bolts, the metal panel frame is slotted) to get room to get the third huge connector unplugged. There are a couple of wire ties that hold the wiring harness under the dash. Once the three huge connecters are unplugged, the wire ties are clipped, the cruise and brake switches are unplugged, and all the wires are loose from the column, you can pull the fuse box up out of the hole through the cowl all the way.

Post by **rspi** » 08 Dec 2020, 19:56