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No,the lift pump contactor is controlled by the Multi-Function Swiitches(MFS) 1 & 2.Theses switches signal the Sequence Control Unit to turn on the pump,when that function is activated. At the top of the contactor panel,there is a box with a plastic over. That is the SCU. Inside that,there are (4) four cards,the power supply board,the seguence logic control board,the coil driver board,and the light control board. More than likely,the driver which controls the lift pump contactor is shorted. That's why the contactor activates,as sooon as the keyswitch is closed. Do you have an email address,where I can send you a schematic?
  • Posted 6 Apr 2007 07:45
  • Modified 6 Apr 2007 09:51 by poster
  • By Truck_Tech
  • joined 30 Mar'07 - 152 messages
  • United States

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