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JLG 40H no proportional controls

Discussion in 'Forklifts/Telehandlers' started by BrownBear, Mar 13, 2020.

  1. BrownBear

    BrownBear Member

    Jan 29, 2020
    Wawa, Ontario
    Baby's first lift, a JLG 40H 1997 with Ford engine and 3 PQ Controls at the platform. s/n 047753030030541

    All the ground controls and platform switch controls work as expected but none of the proportional controls does anything. PO says they worked intermittently and in certain positions before the lift was parked last year. Wiring appears intact and undisturbed. Any suggestions on where to start troubleshooting?
  2. excavator

    excavator Senior Member

    Oct 16, 2006
    Pacific North West
    Check to make sure you're getting voltage to the proportional control dump valve. If I remember right it's located on the right side of the radiator area.