Discussion:
CAT ET4000 - No Left Drive Motor - No Error Codes

Currently Im Working On A Cat ET4000 With Zero Error Codes I have No Documentation on this unit besides a Factory Wiring Diagram.

Currently The unit will operate, but only the right motor will accelerate in forward or reverse. No Error Codes At All. We jacked the truck up with the wheels in the air and tried steering left to right. Zero Action From the Left Drive Motor. Gear Box Appears to be ok.

I have zero experience working on a AC Powered Unit. I have worked on the dozens of the EP20KT Units & are quite familiar with these chassis. What the best way to diagnose the problem? Check voltage at the motor? if so what should it be? or try swapping the controller units between L & R.

Any Documentation would be great Thanks howitt937 at gmail dot com
  • Posted 24 Feb 2014 11:51
  • Discussion started by Howitt
  • Ohio, United States
Showing items 1 - 6 of 6 results.
This is a pretty old thread but how did you replace the motor? Flip unit over?
Thanks.
  • Posted 15 Feb 2022 02:10
  • Reply by Scrid
  • Nebraska, United States
Could you send me the same manual, please
  • Posted 29 Apr 2014 05:25
  • Reply by for_y
  • Sao Paulo, Brazil
thetarget7@ymail.com
Problem Finally Solve - Drive Motor Housing Cracked and When put under a load the unit would Bind Up and Seize. Replaced Motor With New Unit
  • Posted 25 Apr 2014 09:27
  • Reply by Howitt
  • Ohio, United States
I would look closely @ the steer sensor and check it for proper operation.
  • Posted 25 Feb 2014 23:50
  • Reply by RCAV8TOR
  • Alabama, United States
What i used to do all day now takes me all day to do.
It appears the controller might be bad.
The Gearbox is good.
The machine passed the Self Diagnostic. The Steering sensors registers R & L.
The output of the right controller is ~22 VAC
The Left Controller is 1.7-2.1 VAC In a Straight line with a fully depressed pedal.
The left Drive motor will work for a few seconds when turning the steering wheel ~90% Left / Right.
Ill test the motor for shorts & resistance tomorrow If I have time, My next plan is to switch L&R controller
  • Posted 25 Feb 2014 13:01
  • Reply by Howitt
  • Ohio, United States
Hi I sent you an email with controller troubleshooting to get you started. If you need more information let me know and please post your results when you fix the truck. Thanks
  • Posted 24 Feb 2014 13:50
  • Reply by shovel_fx
  • Illinois, United States

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