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Electrical connections under seat found melted wiring

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Old 12-22-2010, 06:56 AM
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Default Electrical connections under seat found melted wiring



I was looking for the Airbag Seat Occupancy connector as I have a passenger side (front) Occupancy Sensor - Resistance too high error and found this. It was taped up and disconnected by someone previously.

Am I correct in saying its off the Heated Seat element, which isnt working on this side? Is this end going to or coming from the seat itself? Its hard to tell as it goes into a large harness.



Also, which connector is the Airbag Seat Occupancy connector? I would have thought it was like the rear seats, a 2 pin blue/white wired connector, found one similar on this side but not on the other side (to compare resistances). But then I found old AW posts which suggested it was the much bigger Red connector further back. Which is it?
Old 12-22-2010, 08:04 AM
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Think I got your answer:
Bentley says that front seats combine seat heaters with occupied seat sensors, esp if it's aseat with side air bag, including Recaro sport seats.

Heater element and occupied sensor is one combined "net" in seat.

Wiring diagram shows 6 pin connector under passenger seat (green, it says?)...4 wires are for seat heater, other 2 should be for seat occupancy.

Seat occupied for passengers side front seat should be 1 black, 1 white wire, according to wiring diagram...part of 6 pin connector under seat.

Last edited by silverd2; 12-22-2010 at 08:09 AM.
Old 12-22-2010, 08:05 AM
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Originally Posted by silverd2
Think I got your answer:
Bentley says that front seats combine seat heaters with occupied seat sensors, esp if it's aseat with side air bag, including Recaro sport seats.

Heater element and occupied sensor is one combined "net" in seat.

Wiring diagram shows 6 pin connector under passenger seat (green, it says?)...4 wires are for seat heater, other 2 should be for seat occupancy.
Arghh, was afraid of that! Im going to have to cut it as far back as possible and run new wires. I wonder why it melted to begin with?
Old 12-22-2010, 08:25 AM
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Originally Posted by mattsimis
Arghh, was afraid of that! Im going to have to cut it as far back as possible and run new wires. I wonder why it melted to begin with?
Dunno...water ever under the seat?

Plus see my edit below...1 black, 1 white supposed to be occupied sensor wires.

Other 4 should be heater and heat temp sensor...1 for heater, 1 for heat temp sensor and 2 ground wires.
Old 12-22-2010, 04:53 PM
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Seat heater element failure is a common Audi problem. They usually short out, leave burned spots on the seat foam. Maybe yours shorted to the point of burning the wires????
Old 12-24-2010, 06:38 AM
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It failed due to a high resistance connection. Just cut the wires out on each side of the connector and make hard connections across it. Unless you plan on taking the seats out again, it will work just as well.

Don't know if this will fix your airbag problem.....but this needs to be corrected first.
Old 12-24-2010, 02:16 PM
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What exactly do you mean "hard connections"? I think you mean to remove the connector and just wire things straight together, a good idea but I read this a day too late!


I traced melted wiring all the way back to the back of the seat where it looked fine. I then split in new, heavier gauge wiring in its place and ran it upto the connection. I left in a short section of the original wire at the connector as I dont have the buttplug type connections to remake the Audi connector (I heat shrinked the short section of original wire of course).

So basically nothing is shorting out anymore and nice insulated wiring all round.. however the heated seat element in the base of the seat (not back) still doesnt work and the airbag still reads high resistance. May have to wire in a resistor instead, was really hoping to avoid that as I nearly always has a passenger (and Im unsure if the airbag works or not with a resistor faking the signal).

Last edited by mattsimis; 12-24-2010 at 02:18 PM.
Old 12-27-2010, 08:30 AM
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The airbag connector is a different connection based on silverd2's post, it's a separate problem.
Old 12-28-2010, 02:20 AM
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Originally Posted by PaulW
The airbag connector is a different connection based on silverd2's post, it's a separate problem.
Thats not at all what I took from his posts, he said they are combined in one 6pin connector, 4 for the heater element and 2 for the Sensor:
"Wiring diagram shows 6 pin connector under passenger seat (green, it says?)...4 wires are for seat heater, other 2 should be for seat occupancy."

If the Occupancy sensor is not this one, which is it?
Old 12-28-2010, 06:00 AM
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I think Paul might have been mixing "occupied" sensor with actual air bag "deployment" wires.
Black and White wires in the 6 pole green plug are definitely the "occupied" sensor wires.
I understand from your first post that the code you get is "occupancy sensor" specific...resistance too high? Maybe there's a problem in the sensor/heater net in the seat itself.


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