Coolant temperature sender resistance

[weta.worker]

Hiya, just doing some tests on this unit and I was hoping someone could tell me the 'hot' readings.

Cold , we've found here

http://forums.quattroworld.com/s4s6/msgs/20985.phtml

"Resistance must be 1500 to 3000 ohms"

But nothing on hot.

Reading out mine it heads towards zero as it warms up (cold reading is around 2300 and heads towards zero as the car warms)

I'm assuming this is what it should be doing (just not sure what it should be reading when hot \ operating temperature)

Cheers

[UrS4boy]

From that post (mine), it says:

"It has NTC characteristics, i.e. its electrical resistance drops as the coolant temperature (engine temperature) increases".

That said, I though that I had found a graph of temperature versus resistance for that. I will look and report back.

[UrS4boy]

That said, I though that I had found a graph of temperature versus resistance for that. I will look and report back.

Quick search showed up some Bosch NTC-type coolant temp data (but not necessarily for our cars) (the 20C value is about right). Put yours in some hot water with a thermometer and check what the resistances are as the water cools from near boiling to room temp. (Don't scald yourself)



and this (non-Bosch):

[S2central.net]

I have the proper graph somewhere in the archives. Gimme a week to find it !