Discussion:
Error Code F3 Inverter Fault and F6 R Motor Offline

I have a Doosan B20T-5 Electric with intermittent Trouble codes F3 Inverter Fault and F6 R motor offline. Does one cause the other to pop up or what causes this codes to display? Also, I know that this lift has a D/D Converter. Is this the same as the inverter? A little help please.
  • Posted 16 Jul 2014 12:20
  • By Tino
  • joined 16 Jul'14 - 2 messages
  • North Carolina, United States
Showing items 1 - 3 of 3 results.
The Power Inverters are located in the back panel, and yes for that model there are 3 power inverters, two traction and one pump. I would suggest you check the power inverters with Ohm meter from Batt+ post to then UVW terminals and check resistance. The do the same tests from Batt- connector to all three phases.
  • Posted 15 Aug 2019 22:42
  • By sirthor1881
  • joined 15 Mar'11 - 24 messages
  • Georgia, United States
we are having the same issue any solution
  • Posted 9 Aug 2019 02:29
  • By doyle_l
  • joined 9 Aug'19 - 1 message
  • Iowa, United States
A little update here. I've been doing a little research and this is what I've found about this piece of equipment;

F3- Inverter Fault actually means drive right module desat/overcurrent
F6- R Motor Offline actually means drive right motor current offset

Also found out that this F/L has 3 inverters - one for each drive motor and one for the pump motor. So, I believe that the right inverter may be defective (F3) and causing the F6 code.

Just gotta find out where the inverters are located and I should be good to go.
  • Posted 17 Jul 2014 05:01
  • By Tino
  • joined 16 Jul'14 - 2 messages
  • North Carolina, United States

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Fact of the week
In Germany, the 9th of November is sometimes called Schicksalstag, the "Day of Fate" because it has been the day for several major historical events, including the horrors of Kristallnacht in 1938 and the fall of the Berlin Wall in 1989.