Consult your factory service manual's wiring diagrams for specific instructions for power and ground for your specific model/year. The only thing that will not work if you swap seats is the memory setting. On mk4, this is controlled in a separate module and you would have to change both the module and wiring harness for it to work.
The main advantage of power seats is that you can adjust height and tilt separately. Only the mk3 Passat manual seats have separate height and tilt adjustments. Mk4, mk5, and mk6 manual seats all use a single lever that adjusts height and tilt together, at the same time. VW power seats are also normally leather. Almost all VW leather has a solid surface but all VW leatherette is perforated for breathability. Leather also smells like leather, leatherette has a neutral smell. As another test, leather is burn resistant whereas leatherette will char and shrink when burned since it's plastic.
You can find used power seats from the high trim level Volkswagen. Depending on the generation, some were called highline, GLX, or package 2 cars. All mk3 Jetta/Passat seats are swappable. All mk4 Golf/Jetta seats are swappable. Mk4 Passat seats are swappable with front Audi A6 seats (B5 and B5.5 have a slightly different side airbag plug under the seat but the same plug at the airbag). Mk5 Jetta/Golf seats are swappable. If you have a 2 door Golf, adding a power seat will remove the easy forward release for rear seat access.
The only North American VW TDI that came with power seats from the factory was the mk5 A5 Jetta with package 2 during model years 2005.5-2006. The 2009-2010 TDI had manual heated leatherette (vinyl) seats standard with no option of power seats. 2005.5 package 2 VW Jetta came with power heated seat w/memory and lumbar on the driver's side and power heated seat w/lumbar on the passenger side (no memory). For 2006, package 2 Jetta TDI had a fold flat manual seat on the passenger side. All other A5 Jetta TDI had vinyl seats. See 1000q: early A5 jetta TDI checklist and 1000q: 2009-2010 Jetta TDI buying checklist for more comparisons and FAQ.
Update: The new 2012+ VW Passat TDI will also have power seats. If your same generation Passat doesn't have power seats it may be possible to add them.
Warning: ground the seat and yourself before working with any wiring! There is a small chance that static electricity could ignite the side airbag in the seat! Read and agree to the TOS Agreement for the full legal disclaimer before proceeding!
hog ring pliers and rings (can substitute zip ties)
clean work gloves
soldering equipment and wire stripper
aftermarket harness adapter (optional)
If you wish to add heated seats you'll have to add a fuse (see 1000q: how to add a circuit), the button, and a retrofit harness (or harness for Golf 4)
First confirm side airbag and seat rail bracket compatibility. I do not
recommend splicing the side airbag harness because this can introduce resistance
and you want to make sure the side airbags work as intended. On some cars,
the harness plug under the seat is different but the plug at the airbag is the
same. On other cars you may be able to de-pin the replacement plug and
re-pin it in the original plug. If you sourced seats from an auto
recycler, make sure they include the pig tail (the other half of the wire
harness) so that you don't have to buy replacement plugs and pins. If you
need to remove any pins, an example of how to use the release tool is shown in
the video below. Most plugs on the seats have a secondary lock which has
to be released to release the pins in addition to using the terminal release
Disconnect the battery by loosening the 10mm nut on the negative terminal. Remove the negative terminal. Put an insulator between the terminal and battery so that they can't touch and then step on the brakes. This will activate the brake lights and discharge any stored electricity,
Remove your old seats. If you have a B5 Passat, see 1000q: VW Passat seat removal for more tips and pictures, other mk4 VW similar. For mk5 cars and mk6 cars, see 1000q: mk5 front and rear seat removal. Before touching any side airbag plugs or wires, always touch a bare metal ground like the door striker pin to discharge static electricity. It's possible for a static discharge from your touch to activate the side airbags!
If the seats do not need reupholstering, skip to the section below "Procedure continued". I bought power seats for cheap but they needed new skins. It's not too hard to reskin seats but it's annoying and time consuming so it's better to buy seats in good condition.
First remove the plastic trim panel. There is a single phillips screw on
each half and some clips/pins that hold it on.
While you're here, note the wiring. Any wiring you see here is for my
car only! Consult your factory service manual for your model/year.
On my car the green plug was for the heated seat,
the small yellow plug was for the seat belt sensor, and the large yellow plug with
lock was for the side airbag plug. The red plug was the power/ground for the
seat motors and the tan plug was for the memory function.
If you wish to test the power seat, connect the power and ground to
12V. The red plug has 2 thick wires, red w/blue stripe is power and brown
is ground. This wiring was for my car only! Your car may be slightly
different so test all wiring yourself.
If you have manual seats, remove the height/tilt lever. Remove the
screw caps and remove the screws (may be T20 torx). Pull out the seatback
tilt and lumbar adjustment knob.
I suggest removing the bottom cushion/skin first since they tend to be easier
to work with. Feel along the side of the bottom
cushion/skin to find the end of the tension loop. Pull it down
to release the clamp and out to remove it. Work along the edge until the seat
cushion is loose. If you have a plug for the heated seat pad there is 1
small white plug and 1 small black plug.
Disconnect them. Also unclip the large green plug for the heating
The cushion may feel glued on but it's just pressed on from use. You should be able to remove the cushion and skin together.
If you want to reskin the seat you have to separate the skin from the
cushion - pry or cut the hog rings
off. I stick needle nose pliers in them to pry them open. During installation, I use zip
ties to secure the skins. You could reuse the hog rings but hog ring pliers will make installing hog rings much
much easier and I didn't have them. Pictured below is a hog ring after removal and the location of the
The seat back is a little harder because hog ring removal is required to get
the cushion off. Feel along the side of the seat back cushion/skin to find the end of the tension loop. Release the seam. Now look inside and you
will see another tension wire on both sides - release them. Flip the skin inside out and roll it
up over the cushion.
You will come to some flaps tied down with hog rings in the front and hooks/wire
supports in the back - release them. I cut away
the old skin for illustration.
The blue arrow in the above picture is the middle wire support. This seat
had 3 wire supports - 1 at the top, 1 in the middle for the hog rings, and one
at the very bottom. The middle one below is designed to be difficult to release off on one side and relatively easy
on the other. After you remove the short wide loop end, you can move the
wire support over to the side to get the long narrow loop side off (shown
below). On all the wire supports, pry open the end loops to release them.
The location of the middle and bottom wire supports is shown below.
There are hog rings in the front of the cushion. Remove them as you
flip the skin up and inside-out. 1 of the 3 rows is shown below.
To remove the headrest trim, just pull it off. The cushion and upholstery should fit around it during removal.
Do not release the lumbar adjustment assembly, just pull the knob off.
It may be tight because of some internal clips so wiggle it back and forth while
pulling it off. Pictured below is the assembly. If you decide to
remove it later, release the cable end and 2x phillips (could be torx) screws at the knob base.
Installation is the reverse of removal. I used zip ties to
replace the hog rings because they are a lot easier to work with. You can
fish them in from either the front or back during installation. Note - the
pic below has an error - the middle wire support actually goes behind the foam
layer but it worked out fine.
In the picture below you can also see the backrest
heating pad wire and its hole in the cushion.
CAUTION: double check the wires against the wire diagram in your factory service manual to confirm which wire is power and which wire is ground! These pictures are for my B5.5 Passat only! Someone may have modified your wiring and your car may be different!
The memory function on the B5 Passat requires more wiring and another control module so I suggest just settling for power and ground to make the seat motors work. Heat and the seat motors use 2 separate plugs. If you need both I'd just buy an aftermarket wire harness adapter with plugs on one side and spade connectors for the fuse box on the other. It should also include the wire harness for the heated seat adjustment buttons.
I wired the seat power to the center console rear 12V plug. It was
faster and easier than running a wire to the fusebox for both front seats.
The power seat motors will only occasionally be used for a few
seconds at a time and the cigarette lighter wire is of sufficient thickness.
See 1000q: Passat center console removal for
tips on removing the center console. You should see the seat wire harness
and 12V plug.
On my car, the red/blue wire was 12V and the brown wire was ground.
Splice your plug into the power wire and run it under the carpeting - the
finished result is shown below. Ground can be any good bare metal ground
or ground wire. Make sure
that the wire is shielded with electrical tape or cloth insulating electrical
tape from the center console. There are some raised areas where it won't
pinch the wires but the edges are sharp so make sure they don't cut the wires.
The rest of installation is the reverse of removal. Reconnect the
battery after all plugs are in place. Always disconnect the negative
terminal on the battery first and reconnect the negative last. As noted
earlier, the memory function won't work without the addition of control modules
which requires additional wiring.
Feel free to ask a question about this article at the myturbodiesel.com Volkswagen TDI forum