Cat Lift Trucks (& Caterpillar) DP55N1:
Error code D-75

Hello everyone. I am going crazy trying to figure out the D-75 code on my Cat 2018 DP55N1 forklift. The error refers to Idler SW Error, however, it does not explains what to do to troubleshoot it. Dealers and all have tried different things and nothing works. The systems, well forklift drives fine, then out of no where the accelerator pedal does not work, but machine can keep going forward or backwards if you change gears, just on idle. When the D-75 code appears it does the above, and for not a certain reason. I so far tested volts and 5.01 is getting to the TPS. But from there on the TOS lever moves but with no response. If i turn machine off and back on, then the accelerator works and the code despair. While driving it again at no specific time, same thing happens. Does anyone knows if this could be a bad TPS?
  • Posted 28 Sep 2024 22:26
  • Discussion started by Jdel
  • Florida, United States
JD
Showing items 1 - 1 of 1 results.
This is an idle validation switch error.
Ecm sees one of the following:
Signal voltage from the throttle pedal is less than 0.6v for 0.25 secs while validation switch is not active.
OR
signal from throttle pedal is greater than 0.95v for 0.25 seconds while idle validation switch IS active.
If this happens, the ecu will debate and ignore throttle inputs.
Usually this is the idle switch failed, wiring is shorted, or switch is out of adjustment.
  • Posted 26 Nov 2024 10:13
  • Reply by IdahoTech
  • Idaho, United States

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