How do I test a water temperature sending unit on a 1984 380sl.

There are 3 coolant temp sensors on that car..

Which one?

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The one that runs to the temp guage in the cluster!

Use an ohmmeter. "Cold" should be about 256 ohms, "operating" temperature should be about 75 ohms.

OHM 110 = 60C
67 = 80C
38 = 100C

I use the 38 ohm as that range is the most accurate b/c it is a neg Thermistor and 100C is easy to read.
Have one in teh tool box with the plug right on it for quicky testng both gauge and sensor.

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A Dalton

I posted the chart here somewhere. Do a search!

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-tp


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