code F only is failed transistor or related wiring

also associated with codes Fr or FL

If code is only ¨F¨?

RJN8,
Code FO

Possible causes:
- Drive motor current limit potentiometers P3 and P4 out of adjustment.
- Programmable feature '8' set to 1 with truck in a ramp application.
- Programmable feature 'a' or '4' set too low for the application.
- Excessive drive motor current due to severe ramps, abuse, or misapplication.
- Current shunt defect:logics defect.

Checks
- Check right current shunt and wires 42 and 29 and connection P2-11 and P2-7 at the logices board.
- Check left current shunt and wires 43 and 25 and connections P2-13 and P2-8 at the logics board.
- Disable programmable feature '8' if ramp application requires more current than set with P3 and P4 current limit potentiometers.
- Determine maximum motor drive current and the time that this current is needed for the application.
- Extend the bypass stall timer. Programmable feature 'A' or the pulsing stall timer. Programmable feature '4' if needed.

Not to hijack your thread, but anyone know Code F O?

'Fr' , 'FL', and F apply to the failure protection circuit and will be displayed if a condition exists that could cause the operator to loose control of the lift truck speed. a short circuit in the drives can cause the logics to deactivate the line contactor and the line contactor is commanded to open to prevent any further issues.

FL does indicate a problem in the left side and is detecting a high voltage on wire 41 emitter.

this is what the troubleshooting chart says for this code:
check the left power transistor circuit
with battery disconnected remove logics cover and check continuity of wire 41 at emmiter of 1TRNL to P2-10 on logic.
if no continuity repair wiring, if continuity replace logics.

i would still look closely at the transistor, it may be bad and causing this code.

FL: Drive problem; voltaje on right drive transistor emitter (wire 41)