Remove back seat 98 volvo s90 - 1998 Volvo S90

Not long and doing it yourself could save you a few hundred dollars from reports I have seen
online.

Please ensure your vehicle is securely supported if you intend doing the work your seld
good luck

That generally means the transmission, and most likely the PNP switch are malfunctioning.

You can typically limp it along by pushing the button on the shifter and moving it from "1" to "P" back and forth a few times in rapid succession, but ultimately you need to replace the PNP switch.

The OEM switch is about $170 and the aftermarket part is about $70. For this sort of thing, I'd use the more expensive factory part.

They're available at FCPGroton, IPDUSA and eEuroparts and other places.
Volvo PNP Switch 960 S90 V90 Genuine Volvo 9466013

Its in the engine bay, all you have to do is take the cap off. For location see here:

http://new.volvocars.com/ownersdocs/1998/1998_SV90/98S90_114.htm

this sensor is located at the end of the block, back side of the block, passenger side, between the firewall and the engine. it is held by 2 six point tork t40 screws. the one on top is very visible, it has a ground wire that attaches to the fire wall. the other one is on the opposite side down below 180 deg apart.

no tools needed,

check for other fasteners

Try running the seats back and forth for their FULL travel. Electrical motors do not like sitting so much. Also get some white "lithium grease" NAPA has the best for about 8.00 with tax. Spray the grease onto the tracks. The motors can use a shot of a lighter medium. Try spraying and running the seats all the way front and all the way back 5 times. Do this once a week after that. This should help your seats to operate all the time.

change out the pluges may have too much carbon on them

not knowing which sensors you have checked, or how you checked them its pretty generic of a question. First is the system fully charged? If you KNOW it is, and you are SURE that the sensors?? are working, then it might be a control head issue. This is not really something that can be checked as a seat of the pants. Which sensors were tested, and how so? and what were the results etc.

Chris