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I did some searching but couldn't come up with a good answer. I have an 06 Aero wagon. My driver's side seat heater got extremely hot one day and then hasn't worked since. I want to swap out my(presumably) burnt out heating pad, but it shows 2 different ones. One is just listed as for the 93. And the other is designated for "sport " seats. What's the difference and how do I know which one I have?
 

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Saab 9-3 2005 Convertible.
I removed the driver seat to see if I could repair the non-working seat heater. A plug dropped off and I cannot see where it goes. Although it seems to be broken, I cannot find the other half.
Does anyone know what this plug does? The wires are attached to the large plug under the seat.
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Thanks Mimmi, can you give me a bit more detail on where this plug in the photo attaches. Sorry but I have searched the whole seat for ages but can't spot anything that matches this plug. I realize it is not something electrical that I m looking for, but perhaps part of the frame on or near to the moving track.
 

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Wonderful. I see exactly where you mean and there is a hole where the little magnet fits. Thanks very much, Mimmi.
I have gone over the whole of the seat heater wiring and all is correct: there is continuity of the actual heating element and the little relay works. The only doubtful bit is the little sensor in the heat pad which I presume is a thermistor: it has infinite resistance i.e. zero continuity,
Any advice on that?
A circuit diagram for the seat heating would be helpful.
 

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You have bad NTC.
Sadly Saab never published NTC diagrams, so you need to measure from another seat.
TECH shows temperature.
Download your own copy of WIS from stickies.
 

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Thank again Mimmi,
I have followed many links for the Saab WIS but been stumped by sites being down etc.
I have searched but only found a generic page which states the value of the NTC thermistor is 5000 ohms at 25 deg C. Does anyone know if this is correct for the Saab? (It's not easy to check the passenger seat for this but I will try it.)
 

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Right seat:
MCC: Measure resistance MCC connector pins 16/17 (left seat NTC is pins 13/17)
ACC: Measure resistance ACC connector pins 23/31 (left seat NTC is pins 21/31).
 

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Right seat:
MCC: Measure resistance MCC connector pins 16/17 (left seat NTC is pins 13/17)
ACC: Measure resistance ACC connector pins 23/31 (left seat NTC is pins 21/31).
I couldn't quite understand this as I do not know to which connectors you are referring. None of mine seem to have these pin numbers.
Anyway I have now thoroughly inspected and checked the base and back heater elements and their wiring. All is well with them.
But there is one wire, which when grounded, operates the relay and this wire is continuous as far as the big plug below the seat but it is not being grounded when the dashboard switch is operated. When manually grounded the seat heater comes on.
The little seat heat indicator light comes on (in any of the 3 positions) but goes off after a few seconds.
 

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Connector is behind MCC/ACC, not under seat.
 

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Solved at last... the thermistor was close up against the element and it now read only 6 ohms. So it was often being shorted out by the element.
With the thermistor inoperative, the circuit in the ACC would not work to send the ground signal to the relay.
Moving it a little way from the element and insulating it with more cloth than originally, did the trick. No new thermistor necessary.
I figured if I persevered long enough I would get to the bottom of it!
 
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