Coolent temp sensor Bad ??
 

How to test to see if I have a bad coolent temp sensor on my 92 400E:confused:

why test it?
 

just replace it!

believe me
 

it costs less to just change it than to test it....

Use a multimeter and check the resistance between the 2 terminals vs the resistance specifications. Which coolant sensor is giving you trouble? There is more than one.

Dumb
Dumber

I agree, test it with a multi meter its easy.

I would suggest testing at room temp. You can simulate other temps by putting it in the freezer, etc.

Someone else will have the values.

Aux fan not comming on, replaced bad strip fuse with a inline blade fuse, now the fans kick on high if I pull the plug on coolent temp sensor, and it will cycle on with the AC but the car got hot last week in bumper to bumper traffic and the fans did not come on?? The sensor I pulled the wire off to test the fans is the one on the front of the engine all the way to the right.

How hot did it get? The fans are supposed to come on at 105c.

it was readingabout a .25 inch from the 120 mark??