Opportunity Status Report, June 22, 2017: The rover experienced a left-front wheel steering actuator stall on Sol 4750 (June 4, 2017), leaving the wheel toed out by 33 degrees. Our initial attempts to straighten the wheel failed to yield any results and were suggestive of a mechanical cause for the stalls (in the steering actuator). Fortunately, however a repeat of the diagnostics on Sol 4763 (June 17, 2017), added a twist that may have made a difference….
This very good result was tempered by the fact that we still do not know for certain what the cause of the stalls was and whether the problem could reoccur. Therefore, Opportunity will be exercising a precautionary partial moratorium on usage of the steering actuators for the foreseeable future. Specifically, this directs no front usage of steering actuators and only rear usage as circumstances might demand. Instead, tank turning and steering will be used wherever possible… [More at link; click image to enlarge it]