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Deere 200c unidentified switch

Mallard · 2026-04-09 17:47

I recently bought a Deere 200c excavator and am having a friend go through it and get it good enough to work, as time goes on I’ll work on getting all the little things corrected and back to 100% this will be used on our tree farm and around the house. I’ve been reading here and the manuals for the last few months learning all I can about it and then looking at the machine trying to make sure I understand everything about it. I have run across a switch, under the left arm rest in front of the radio and beside the travel alarm cancel switch that I cannot identify. I can find no mention of it in any manual and no luck with chat gpt either. Any idea what it is for?

Replies10
  1. #1Deere500a2026-04-09 18:07

    Aftermarket part store switch for lights,fan etc

  2. #2DDoug2026-04-09 19:42

    and it appears to be snapped off in the "on" position as well.

  3. #3Mallard2026-04-09 20:56

    I agree it’s an aftermarket switch but it appears to be an OEM logo above it. That made me think the OEM switch broke and was replaced with an aftermarket switch.

  4. #4Nige2026-04-09 21:14

    If the logo refers to the switch then it appears to be some kind of low temperature engine starting aid. This would indicate either an air intake heater or ether.

  5. #5John C.2026-04-10 01:30

    Does the machine have extra piping from the main control valve to the end of the stick?

  6. #6mg23612026-04-10 05:00

    The label symbol itself is for the start aid. That switch is not factory. It may have been installed to replace the factory switch or it is for something else entirely.

  7. #7Mallard2026-04-10 07:48

    Yes, it has the two way aux lines but they are capped at the end of the stick. There is a 2 way foot peddle on the right side. The right aux line Y’s at the base of the boom. One goes to a shut off valve and then to tank and the other to the valve bank.

  8. #8Mallard2026-04-10 07:53

    Thanks mg, that looks to be it. I havnt seen the ether bottle or mount yet while looking everything over. Do you know where it would be. My 650H dozer has ether assist and is almost the same year, I assume the bottle and mount would look identical, is this correct?

  9. #9Deere500a2026-04-10 15:12

    On this 200c decal is there but hole blanked off I think it's a hole used it's a cheap switch to replace if it has power flip it off see maybe for aux

  10. #10John C.2026-04-10 21:22

    You have what people in this area call combo hydraulics. It means you shift between two way flow to run a thumb or grapple and one way flow to run a compactor or breaker. It was common in the time frame of your machine to use any extra hole in the dash to install a toggle switch in to shift between operating modes. If you can look under the switch to see the colors of the wires you can probably spot one of them going to the valve.