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NTC stands for Negative Temperature Coefficient. It's a resistor whose resistance goes down based on temperature. Located in middle of intake manifold (where it bolts to the head, between runners 2 and 3) on any 16v car. Has a blueish-green plug, IIRC (color may be obscured by black Bosch connector). Tells the ECU how hot the coolant (and thus the block) is.
 

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The correct name for the part is Negative Temperature Coefficient Resistor.
SAAB Service and Parts literature never referred to it as a "Sensor".
When the cars were new, we all called it the NTC Resistor. It is the only NTC resistor in the car.
 

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I hadn't thought of that.
The adjustable heated Seats were not available when I went to LH School in 1985. At that time, they told us that there was only one NTC and that's why they didn't bother to call it a "Sensor".
 

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<pet peeve>
Which is precisely why it's a daft name to use to describe the coolant temp sensor. All temp sensors are either NTC or PTC. (Resistance decreases or increases as temp rises).
But if you called it coolant temp sensor, one might be confused it with something PTC when they whip out their multimeter to test it :D
 

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But if you called it coolant temp sensor, one might be confused it with something PTC when they whip out their multimeter to test it :D
Difficult to test it properly without a list of what resistances correspond to what temperatures - whichever way they go... OTOH, if you're just doing a quick'n'dirty test, it's more important that the change is smooth, without any sudden changes or leaps to open-circuit or dead short - again, whichever way...
 

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I don't believe they are. Just a simple thermostatic switch. No thermistor there.
Depends which kind you have. The earlier c900s and maybe all c900s in some markets had the "Aut. Heated Seats" with the thermostatic switch in the cushion as you describe. When the seat-foam gets old, these button-shaped switches poke me uncomfortably. Later c900s (In USA) and 9000s had heated seats (at least the driver's seat) with what some call a "rheostat". This was not a rheostat. It was really a thermostat in a three-position-plus-off switch that read temperature from a thermistor in the seat cushion and compared it to a set point (setting 0, 1, 2, or 3 on the switch). I just retrofitted one to my driver's seat after soldering the broken element back together in 8 places. Bless the good man who invented heat-shrink tubing! My bµm is toasty.
 

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I have a 2005 Saab 9-3 convertible.
There are NTC thermistors in my heated seats (this is used by the circuitry in the ACC to regulate the seat heater temperature).
PLEASE...does anyone know what the nominal resistance of this thermistor should be (at 25 deg C)
Alan
 
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