If you have a Heidenhain DRO, maybe a 731B model - that's the 2-axis imperial/metric with Memofix function - then note that when a bright red light comes on and one (or both) of your axes freeze up, seemingly stuck forever.... that's the Memofix switch having been knocked onto its "red" setting...
The cure is to put the switch back to the green mark, NOT to spend over an hour trying to clean the DRO unit, then fretting about the cost of a replacement scale.....
HTH!
