code 16
Traction motor, stall timer

Situation
Display:"16". All truck operations inhibited. Line contactor OPEN and steering contactor HOLD.

Possible cause
Stall current flowed more than set time (#20) in traction motor, faulty traction inverter current sensor, shorted harness
wiring, faulty traction inverter DSP card, faulty logic unit.

How the error code is triggered
Stall timer set time (set by Setup Option #20) is measured while stalling.

I would check the parking brake and make sure it is not applied.
check for any other problems that may be causing a stalling effect like wheel adjustments being too tight etc.

Once you rule this out then start troujbleshooting the control circuits.

you will need the troubleshooting manual to troubleshoot this code, there are many steps in voltage checks to take to do this effectively.