Power seat movement ... slow, intermittent.

[maxPower]

Originally Posted by Laird Scooby

Out of interest, did you test the seat in the breakers/junk yard before removing it? I'm wondering if that was part of the reason it was in there. Not sure about the laws where you live but here in the UK we have to have an MoT each year which is a safety test for want of a better expression. If the drivers seat can't be adjusted so the driver can reach the pedals etc then it's a fail point. It's possible if a similar rule exists where you are that this is why the car was in the yard and you struck unlucky with it.

That aside, the symptoms you suggest point to a fault in the ECU - the big flat box underneath the seat. If you (or someone you know) knows about electronics, it might pay to have a look inside for dry joints.

Just read your latest post about going for another seat - that might be the answer. If it works, you can swap the cushions and/or covers to get the colour scheme you want/need so colour isn't important.

I didn't bring a battery to test it. I'm learning

I will look at the ECU again before starting the job of tearing down / swapping parts to the manual seat. I am leaning, however, to just going ahead and going straight manual if the parts are swappable.

I'd like to swap:

1. Full seat back from the powered to the manual, as the lumbar in the manual I have is faulty and I'll need to swap the foam and cover anyway. (can I convert the power driven seat back position to using the handle?)

2. Move the foam and leather from the power seat bottom to the manual seat bottom.

3. I will test the heater in the seat bottom and probably just leave the heater cables and springs there. They look decent.

[Laird Scooby]

It can certainly be done. Be methodical, i can give you pointers but none specific to the Volvo seats as i haven't done one yet, got some front covers from a similar year to mine to replace the old worn, ripped covers.

There will almost certainly be a hidden fixing in the backreast, you'll have to roll the cover down the backrest (or up, depending how you view it) once everything else is loose to find it, it pulls the contour in on the front.

General pointers - work with the seat upside down, there will be hog-rings that you'll need pliers to remove and pushing down on the cushion as you try will make life easier. Also you need to remove the headrest before you start, assuming the 960 seats and 740 seats are the same, there are hidden buttons about 3-4" down from the top of the seat in line with the headrest legs. Push them in and remove the headrest.

Take plenty of photos including heated seat connectors and so on.

Good luck!

[maxPower]

Well, I may be up for an award.

I put the 740 seats into the car (they aren't in bad shape, leather matches too) for now. Wanted to give myself some time before taking on the swap project.

Curious to see if the heated seat function works, I hooked up the battery I'd been using to work on the power seat.

The battery is/nearly dead.

That would explain why I was getting functionality from the power seat that just 'went away' with a few seconds time. The confusing part was there was just enough power to turn the motor for it to turn the cable, but not enough to power the chair movement. The back of the chair movement must have used a very minor amount of power.

I must have rebuilt the bottom of that seat 8 to 10 times looking for clues as to what was going on. At least I know it well now.

Wonder what will happen when I hook it up to the charged battery...

[maxPower]

With a charged battery the seat now operates flawlessly.

I rebuilt this I don't know how many times, and the cables are all nice and lubed up now. So it will go in as power. I'll find somewhere to stash the manual 740 seat as a doomsday backup.

Thanks again for the help.

[Laird Scooby]

Originally Posted by maxPower

With a charged battery the seat now operates flawlessly.

I rebuilt this I don't know how many times, and the cables are all nice and lubed up now. So it will go in as power. I'll find somewhere to stash the manual 740 seat as a doomsday backup.

Thanks again for the help.

A flat (or even slightly low) battery causes all kinds of confusion to ECUs, including engine management ECUs and obviously seat ECUs too although it might have only just had enough juice to move the seat at the time.

Loose or sometimes even just old fuses can also creat havoc in a similar way, glad it's all sorted now anyway!