Have had this problem for a while but would like to solve it. Haven't seen anything on the forum about it.
First off it is a QT20 (1984) with Mazatrol T-1 Mitsubishi controls

On start up if you are in gear 2 and make a gear change to 1, the gear box shifts ok, but the spindle makes about 1 revolution then stops momentarily and repeats this cycle till a reset is made. There are no alarms however the gear reads "0" on the CRT. This is with parameter SD2 set to 1 (manual shift)
At this point attempting to shift to gear 2 produces Invalid entry.

Changing the SD2 parameter to 2 (automatic) allows the change to gear 2 and there is full operation of the spindle. Gear 2 is read on the CRT.

Gear changing to gear 1 at this point produces the same result of stop and start above.

My work around is to program everything in gear 2 but this limits my capabilities.

Thanks for any suggestions that you could give me.
daveh06033