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Dead Parrot · 10-03-2021, 09:18 AM

Grounding the sender wire from the gauge should give a full scale reading. That part sounds like it is working.

Make sure the sender is a gauge sender and not an idiot light sender.
Senders from different year ranges have different temp/resistance curves. Many aftermarket senders don't match the OEM versions. Not unheard of for the parts store to sell an idiot light sender as a gauge sender. They often look similar.

If you have an Ohm meter, check the resistance of the sender cold. Should be high but not infinite. Depending on sender, somewhere between 2500 and 900. Then check hot. Should be much lower. Between 100 and 40, IIRC.

This issue is fairly common. Several threads on the subject.

10-03-2021, 09:18 AM	#5
Dead Parrot Registered User Join Date: Aug 2012 Location: Oklahoma City, OK Posts: 2,486	Re: Temp sensor/ gauge not reading.... Grounding the sender wire from the gauge should give a full scale reading. That part sounds like it is working. Make sure the sender is a gauge sender and not an idiot light sender. Senders from different year ranges have different temp/resistance curves. Many aftermarket senders don't match the OEM versions. Not unheard of for the parts store to sell an idiot light sender as a gauge sender. They often look similar. If you have an Ohm meter, check the resistance of the sender cold. Should be high but not infinite. Depending on sender, somewhere between 2500 and 900. Then check hot. Should be much lower. Between 100 and 40, IIRC. This issue is fairly common. Several threads on the subject.