Yale ERP030THN36TQ090:
Fault code 91 pump motor temp high

I recently replaced some components on the drive board for the hydraulic pump (lift pump). After getting the forklift operational again, I now have a code 91 (pump motor temp high). I have read that the sensor could be grounded or bad. Does anyone know where the sensor is located? Or if there's a way to bypass? The motor is definitely not hot, as it is displayed immediately after turning the key on. After operating the forklift for over an hour, the motor is still not hot and nothing seems to be affected by the fault code, but I believe I am unable to change to the modes while this fault is active.

Any help would be greatly appreciated
  • Posted 13 Mar 2021 02:25
  • Discussion started by Cody_Parsons
  • Washington, United States
Cody Parsons
Showing items 1 - 3 of 3 results.
awesome, glad you got that sorted out
yep, those machines were pretty nice , will make a good unit for someone that needs a tight turning smaller lift.
  • Posted 16 Mar 2021 08:21
  • Reply by swoop223
  • North Carolina, United States
You've been swooped!
swoop223@gmail.com
I'd really like to say that I didn't have two plugs mixed up....buuuuuut.....

Switched them around and everything is operating as it should.

Thank you for the quick reply!

I now have a 2008 Yale up for grabs if anyone is interested haha
  • Posted 15 Mar 2021 23:15
  • Modified 15 Mar 2021 23:15 by poster
  • Reply by Cody_Parsons
  • Washington, United States
Cody Parsons
If your unit has a AC or DC controlled motor there is a temp sensor inside the motor that can go bad. Note: there is also a temp sensor inside the motor controller. Now the following troubleshooting information only suggests to test the motor temp and replace the sensor OR the problem may be in the dash display. I would check the motor sensor and wiring harness's and connectors before i went to the dash display replacement.

-Fault code 91-
Probable Causes and Test Procedures
* Use dash display diagnostics to verify motor overtemperature
switch is activated.
* Reduce truck operation until motor cools.
* If fault is signaled with cold motor, use dash display
diagnostic to verify motor temperature.
Replace motor temperature sensor.
Replace dash display.
  • Posted 15 Mar 2021 21:37
  • Reply by swoop223
  • North Carolina, United States
You've been swooped!
swoop223@gmail.com

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