2001 V70 power seats working intermittently

[superjodz]

I've been having a problem for a while now with the power seats in our V70. They seem to stop working intermittently. When they stop working it's all the controls, not just one direction or motor. No clicking, no nothing as if the power to the switches has been cut off. But since it's intermittent it can't be a fuse.

What's been happening the last few mornings is that I'll get in the car and I'm able to move the seat. I'll move it a few times, then put the car in gear, and they stop working---which I've always assumed is a safeguard---but then I'll stop the car, put it in park and they still won't work and won't work for the rest of the day basically. I managed to replicate this a few times so I thought it was maybe the fault of whatever circuit/module/switch prevents you from moving the seat when the car is not in park possibly sticking.

But today I got in the car, moved the seat a few times, paused for a second, then tried again and it stopped working. I hadn't even started the car yet (I think).

Is there a safety feature that prevents the seats from moving when the car is out of park??

I can't see it being anything in the power supply like a fuse/switch/relay?

This car has been an electrical/computer nightmare ever since we bought it.

[jda2000]

if the problem is intermittent,I suspect dirty or worn out seat module contacts.

Try taking it apart and cleaning it or try a used unit from the wreck yard. And yes, volvos can be a nightmare when the electrical gremlins are present

[superjodz]

Yeah I was thinking about the power seat module and if it's dirty or worn out contacts it would have to be the ones that supply the PSM because when it stops working, like I said all the function stops, not just one direction.

I was looking at the power seat wiring diagrams and there's something that might support my theory about the safety permissive when the vehicles is not in park. On the driver seat diagram there is a relay on the CEM numbered CMI22 (part 2/29) that has a switch inside it. If I could find out what that part does then I could determine if it's the issue. That part doesn't exist on the passenger seat, which makes sense because it wouldn't have the same safety permissive.

I'm definitely not ruling out dirty or worn contacts though because I constantly hear about that on this board.

[cdnbluez]

I had the same problem with an '02 V70 I used to own. I bought the car used, and the driver's seat didn't move at all. I figured it was fixable, so I started to look around for a used control module. I bought an entire seat out of an S80, and swapped the control. Like your car, the seat worked fine for the first 10 seconds when you enter the car. After the initial 10 seconds you couldn't adjust the seat. From what I understand, you don't need to have the key in the ignition, the seat will work for 10 seconds. It's a "courtesy" period which allows drivers to adjust the seat before you start the car. After about 10 seconds, the car's main "computer" kicks in and it's not detecting your power seat module. My mechanic said the dealer would have to run diagnostics and re-program the "computer" to accept the swapped seat control we put in my car. I went to the dealer and they went on about how they would have to scan/update/reprogram yada yada $500-700 later. So I left it the way it was. I basically programmed my seating position and my wife's seating position into memory. As soon as you opened the door you had to quickly press the memory button corresponding to your seating position, or else drive around real uncomfortable for the day. If you let the car sit awhile, you could re-adjust it (pita). Wife wrote it off, bad tranny and all.

[JRL]

You need a new module
Cheap used from Erie

[Figgie57]

I had the exact same symptoms and after researching a new dealer module at $538 or a lifetime warranty module from Erie Vovo for $150. I went with Erie Vovo. The first unit they sent did not work, but the quickly sent 2 more modules to try, the second one I put in works fine. They sent a return label to return the 2 other modules. Be sure to follow instructions for disconnect, reconnect battery so you don't create other module issues.

[JRL]

BTW,they're working intermittently, not
they're not working intermittently
That's a double negative

[J5T]

I have the issue of the driver seat will only work for about 45 sec once the vehicle is woken up and then will not work again until the modules go to sleep and woken up again in the 2002 XC and the 2001 V70T5. So it is possible to buy a used PSM and it is plug it up and no need for a software load from the dealer? If so, do you have to get a PSM from the same model and year vehicle? Meaning will a S60 2002 work in a V70 2001.

If replacing this module do you need to disconnect the battery, touch the terminals, say 3 hail Marys, cross your fingers, etc. Danke.

[LeoTeoh]

I got a same problem for my driver seat, after i saw all Discuss for my understand that mean has 2 way to solve that problem is re-programing the "computer" or get a used power seat module, can i have more information to follow instructions for disconnect, reconnect battery so you don't create other module issues ? thanks a lot

[Figgie57]

I am sure there is battery disconnect, reconnect procedures on this site,, but I found a good procedure I use on "Howard's Volvo" site.