I see this was back in 2017. I'll post my observations for anyone working through a G2 code who may read this in future. This applies to all 4150 & 4250 Raymond dock stockers and Toyota 8BNCU as well.

I would suggest checking the prox sensor, position and gap, as well as the sensor plate first - as the OP did.

Second I would suggest checking the condition of the woodruff keys at the top of the steer spindle. These wear out, as does the top hub plate itself which allows for excessive movement when steering to full lock - particularly to the right from what I've observed.

In this case it seems the new VM resolved the issue for the OP.