the 42 is generated when the cpu sees the 90% speed sw. on the ets bd. out of tolerance. this happens on acceleration. there are a number of small speed bds. plugged into the ets bd. there is a pot on top of each bd. basically you look at motion averages to see when the 90% relay picked and adjust the pot. If I remember correctly counter clockwise makes the board pick at a higher speed. so at 90% of contract you should pick the relay. Also the fault can be generated by a faulty position encoder, or encoder coupling.
