Yes, I had the engine running. Did not just have the key on. Also in 4WD. When I switched back to 2WD the vacuum dropped to zero. I'll need to do a test, but I suspect the grounding for the two wires is controlled by the switch in the cab. That same switch controls the transaxil also. The transaxil does work for 4 X 4 as I currently use the manual method for 4 WD. Thank-you for your interest.

 

This sounds like it's going to get involved. For that reason, you should start your own thread to avoid confusion with the OP's topic here. Also, be sure to include year, make, model, engine, etc. of your vehicle.

 

Have not fiqured out how to start a new thread, only comment on existing ones. Thread tools does not have a mechanism to start a new thread.

 

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