What's not so great is that once in a while will these elements break.
The question is when,not if. The probability increases with the cars mileage.
Anyway I own a Seat Ibiza car, it is very close to the Volkswagen Polo and the Skoda Fabia. The seats are probably very similar over the whole VAG line.
My car is from 1998.
Step 1: Tools Required
Socket set (Not really, but there are some nuts and bolts)
Torx Screw driver (bits)
AMP Connector disassembly tool
I did not know that this tool was needed when I started this project.
After some thought I decided to sacrifice my 0.9mm feeler blade. The feeler blade was grinded down to fit into the inserts for the disassembly tool. Note that two pieces are needed.
Step 2: Remove Front Seat From Car
1. Remove the head rest
2. Thrust the seat fully forward
3. Remove the plastic rail guard, it is quite easy to unclip it.
4. Thrust the seat backward
5. Just below the front seat is a stop screw/nut
6. Remove the stop screw
7. Thrust the chair further back and it will come loose
8. Unclip the heater cable that comes up through the floor.
9. Lift the seat out of the car
Step 3: Disconnect Back Heater Element
2. Write down the cable colors and connector pin numbers for the back heater element
3. Insert your two pieces or the connector removal tool into the connector house.
4. With some persuasion will the contact element leave the connector house
Step 4: Remove Side Panels and Screws
The back locking bolt has a plastic piece that is locked with a Torx screw. Remove the screw and the plastic cylinder
Step 5: Remove Seat Belt Lock
Take a fixed spanner and use some force
Step 6: Remove Back Plastic Gables
The gables are locked by some plastic pins.
The pins lock like small circles in the plastic. There are three lock pins in each gable.
Push the pins into the seat with a screwdriver.
The gable comes off quite easy when the lock pins are removed.
The back angle adjuster rod makes it more difficult to remove the gable. I left it on the back, but I rotated it around the rod
Step 7: Remove Back
It is now possible to separate the seat and the back
Step 8: Remove the Seat Tray
Remove the screw and the tray comes off.
Step 9: Loosen Steel Wire Holding Chair Upholstery
The steel wire is fixed by the plastic cylinders removed in step 3. The steel wire is easily pulled of
Step 10: Remove the Upholstery
I used a screwdriver to remove the upholstery from the back of the seat structure. There are some sharp metal parts that cut into the plastic "hem", or plastic edge sewn to the upholstery.
The seat padding is now free from the structure, but the upholstery is still fixed to the padding.
There are three steel wires holding the upholstery to the padding, these wires come loose by compressing the padding.
Step 11: Reassembly
Place the new heating element on the padding, but do keep the glue protection paper.
Replace the upholstery steel wires
Step 12: Fixate the Heater Element to the Padding
Remove the protection papers.
Step 13: Final Reassembly
Remember to use thread fixation compound when replacing the seat belt lock.