Thermistor part number

Krazykraut · Post by **Krazykraut** » Wed Aug 22, 2018 8:18 pm

Sorry if this has been answered, but a search for "Thermistor" or "Interior temperature" didn't turn up anything useful: does anyone have a part number or specs for the little interior temp sensor by the steering column? I saw a post that has the specs (1.2kOhm at 20C, 500 Ohm at 40C), so I went to Digikey for a thermistor with those characteristics, and found https://www.digikey.com/product-detail/ ... ND/2230721
Datasheet looks like this would be the one, but before I pull the plug and spend a whopping US$1.11 on the part, I was wondering if someone can confirm or point to a different part.
I found the wire, and when I short it with a 1.6K resistor it shows a valid temperature instead of the -26C, so I know that bit is good.
Thanks!

Post by **Growlerbearnz** » Fri Aug 24, 2018 2:02 pm

From all the replies it looks like you're going to have to try it and see! Let us know if it works and I'll put this in the TRL. I know that a broken temperature gauge is fairly common.

Krazykraut · Post by **Krazykraut** » Fri Aug 24, 2018 7:14 pm

In the the Chassis_Electrical manual I found:

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Approx. 1.2 at 20°C (68°F) Approx. 1.5 at 40°C (104°F)

I believe that means we need a PTC (positive temperature coefficient) type of thermistor, so the above link is no good. I've been browsing my electronics supplier, Digikey, but haven't found one that would fit. I think I'll hook up a trim potentiometer to verify the curve first, before ordering a part.

Post by **Growlerbearnz** » Fri Aug 24, 2018 9:46 pm

Hmm. The manual might be incorrect; PTC thermistors have a distinctly non-linear response, it would be an odd thing to use as a temperature sensor. Still, test it with a potentiometer and see what you get.