Power seat not working

Jeff Kraker · Post by **Jeff Kraker** » 30 Jun 2012, 17:39

I replaced the control module and installed a different seat. Passenger seat still will not move. Checked the fuse #40 and swapped with #39 and it is good. Looking at the wiring from the seat to the fuse block. Not sure how test the harness for power etc. Can't open the wire diagram on this site / PDF error. 1998 V79R

Thanks

Jeff

Post by **JRL** » 30 Jun 2012, 17:53

What do you mean by the control module, the actual seat switch?
They do go bad all the time

Jeff Kraker · Post by **Jeff Kraker** » 01 Jul 2012, 16:11

No, I did not replace the switch, instead replaced the whole seat with one from a donor car. I suppose that one could have a bad switch as well. Is the seat controller the black box under the seat? the seat in my 1994 850 does not have this box leading me to believe that the seat controller may be located somewhere else and that the black box has a different purpose. How would I verify the switch's viability? Got the wiring diagram to open after downloading, but does not have much info on the power seat system.
Thank you for your help
Jeff

Jeff Kraker · Post by **Jeff Kraker** » 01 Jul 2012, 22:20

Looking under the glove box and under the drivers side dash, not seeing what should be the power seat controller. Following the wires from the pass. side. seat they lead up under the top of the dash....

Jeff Kraker · Post by **Jeff Kraker** » 02 Jul 2012, 17:38

Stopped by Borton Volvo and the parts tech printed me a seat parts schematic. Control unit is under the seat mounted to the seat frame. Only option now is to swap known good parts to see if I can pinpoint the problem. if it is in the wiring from the fuseblock to the seat, that could be hard to trace.

Post by **BEJinFbk** » 02 Jul 2012, 22:27

Are you talking about the passenger seat?
On my '98 R, the pass side has no memory
and I'm pretty sure there's not a controller, either.
The only black box under that side is the amp for the stereo.

Look for a 2 wire connector to the seat switch with larger gauge wires.
If I'm right, you should see 12 volts and ground on them when the key is on.
But I could be wrong...I can't find diagrams to confirm.

Jeff Kraker · Post by **Jeff Kraker** » 03 Jul 2012, 07:22

You are correct, Sir! the tech at Borton printed the drivers side seat for me, discovered that when I got home. I will look at the wires and see if I have current. Temps in the high 90's here in Minneapolis so it may have to wait until the weekend. I have a hard time believing that both switches would be bad, but it is a possibility. I have a donor saffron 98R that I took a motor from 4 years ago and am using parts from that car. Jeff

nascenta · Post by **nascenta** » 15 May 2013, 15:16

I don't have any solution to this poster's situation but recently my daughter's 1994 850 driver seat stopped working. I tried to get error codes through the engine module but nothing came up. Swapped switch panels (the controls to the side of the seat) with another 850. The swapped switches all worked on her seat. Her switches didn't work in the other Volvo. I opened her switch panel up and discovered that the cord was separated from the bus. Reconnected them and everything works again. I guess she had something stuck under the seat and when she moved the seat it pulled the cord/wire out of the bus. Something to be aware of..

Post by **abscate** » 15 May 2013, 19:51

If my 99 sits for a couple weeks at the airport, the seat can be sticky...if I bump it a bit, the power function is restored.

jayandally · Post by **jayandally** » 30 Aug 2013, 20:44

I am also having power seat issues on my 1998 S70 GLT. Can someone tell me where the seat control module is located?

Thanks.