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Seventy Two · 07-03-2020, 08:38 AM

Re Set: This is not a cold case just yet.
I went back through this thread and decided to divide and conquer the 20DG lead from the sensor back to the dash.
I separated the wiring harness at the bulk head and tested the 20DG from the sensor end to the engine side of the bulk head. I got 0.7 ohms and neither end grounded out. Perfect!
Then I checked the 20DG connector on the inner side (cab) of the bulk head connector to ground and got 134.8 ohms! The 20DG wire inside the cab is virtually grounded. But to where? According to the standard wiring diagrams the 20DG wire from the bulk head should go directly to the ignition switch and then onto the gauge cluster.
I will track this down next but until then, can anyone clarify how the wiring should look at the ignition switch? I find the wiring diagrams a little vague in this regard. A picture is worth a thousand words right.

07-03-2020, 08:38 AM	#80
Seventy Two Registered User Join Date: Aug 2010 Location: Grande Prairie Alberta Posts: 105	Re: Temperture gauge is pegged on high Re Set: This is not a cold case just yet. I went back through this thread and decided to divide and conquer the 20DG lead from the sensor back to the dash. I separated the wiring harness at the bulk head and tested the 20DG from the sensor end to the engine side of the bulk head. I got 0.7 ohms and neither end grounded out. Perfect! Then I checked the 20DG connector on the inner side (cab) of the bulk head connector to ground and got 134.8 ohms! The 20DG wire inside the cab is virtually grounded. But to where? According to the standard wiring diagrams the 20DG wire from the bulk head should go directly to the ignition switch and then onto the gauge cluster. I will track this down next but until then, can anyone clarify how the wiring should look at the ignition switch? I find the wiring diagrams a little vague in this regard. A picture is worth a thousand words right.