F 350 4X4 won't come out of 4WD Low

1935 FORD F-350
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SHEEPMAN 1234
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I received a recomendation earlier on this forum and need more. I believe that I have found the problem. I removed the manual Shift on the Fly switch and believe that it is not functioning correctly. With the plug removed from the back regardless of the manual switch position there is continuity between the two outside posts and the two outside posts. It is as if the two center posts are a circuit and two outside posts are a circuit. Regardless of where I move the switch it remains the same.

I feel that unless there is an electronic component int the switch that ativates when the switch is powered this switch is not functioning as rotation changes nothing. I have taken it apart and find nothing obviously wrong. I don't dare simply jumper the wire side of the plug as there are resistors in the switch that must drop the voltage. Jumpering possibly could pop something in the computer.

I simply do not want to spend $44.00 for a switch and find my thinking screwed up and still can't get it out of 4WD. Any help will be appreciated.

2001 F 350 Diesel - Auto trans _ Crewcab - Dually
Jun 28, 2007 at 4:20 PM
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JWALTH02
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Have you tried changing it while it's in neutral?
Jun 28, 2007 at 5:17 PM
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SHEEPMAN 1234
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Yes I have. I've also checked the relays, although due to the non-marking on the relay positions I can not be sure which 2 of the four are for the 4WD. The relays never transfer. Presently the switch is removed and sitting on my kitchen table. My question is regarding the switch itself. Sitting unpowered it never changes the continuity of the output terminals.
Jun 28, 2007 at 5:36 PM
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JWALTH02
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What is the reading you get when you're checking for the continuity?
Jun 28, 2007 at 6:50 PM
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SHEEPMAN 1234
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Thanks for the responses. With the switch in 2 WD, there are 400 Ohms between the two center terminals and 0 Ohms between the two outer terminals.

With the switch in 4 WD High, there is 0 ohms between both the two center terminals and the two outer terminals.

With the switch in 4 WD Low, there are 4000 ohms between the two center terminals and 0 ohms between the two outer terminals.

One of the reasons I am concerned is that in addition to the 4 WD problems, recently the air conditioning switches itself from high aircondition to defrost without the switch being touched.
Jun 28, 2007 at 7:25 PM
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JWALTH02
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Have you considered an exorcist?

Check your wires going from all the connections for as far as you can and check for damage, and what I would suggest if that doesn't come up with anything, get into your nearest junkyard (or favorite) and find a 4x4 switch, take your voltmeter with you and test that switch to see what resistance it gives. If it's drastically different I'd buy it and swap them out then take it for a test drive.
Jun 29, 2007 at 8:53 AM