Leon Speed

It works fine, that is the temp gauge does, but what are good resistance values for the Temp I sensor? I measured and got 623 Ohm between both pins and infinite resistance between each of the pins and ground.

Leon Speed

One more try

Bill Ball

This sensor works on a change in resistance between the pins to provide engine temp signal to the instrument panel gauge. 623 ohms is higher than the stated range for temp I and would be a very cold temp. Does your gauge stay pegged at the low end?

Leon Speed

Ah, ok, are the specs somewhere in the WSM? The temp gauge normally goes to about 82-ish degrees C. 623 ohms is at room temp of about 20 C.

fraggle

Has anyone done some nice testing and created plots with TEMP vs RESISTANCE?

Bill Ball

Yes, in a book on the diagnosis of the 89 instrument cluster that is on Jim Morehouse's Tech Pub CD. There is a test procedure that allows you to read out the values it is seeing on the instrument panel.

Leon Speed

Great! Now that I see it I remember testing this a few years ago. Looks like 623 Ohm at 20 degrees C might be in line with these values. Thanks.

Bill Ball

Yes, could be normal. I thought there must be some malfunction or you wouldn't ask. Anyway, you can compare resistance and gauge readings to an IR gun on the water bridge.

Leon Speed

Right. Just covering all bases during my top end and tb refresh.