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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In March 2002, identical twins in Finland died on the same day in similar accidents within hours of each other. A 70-year-old man was killed by a truck while cycling; hours later, his twin brother was killed by a truck on the same road, about a mile away, before the family had been informed of the first accident.