X-Axis self test issue
Hello, I've had my Prusa MINI for a few years, and in the past year or so it cannot pass the X-Axis self test. My prints have been mostly satisfactory so I ignored it for awhile, but it seems there may be a recent firmware update that now nags me every time I start a print, so I've taken a closer crack at diagnosing.
No matter what I've tried so far, it consistently fails "rew X-Axis u/50 mm/s", landing above the target <182,192> range.
1902.452s [INFO - Selftest:10] X-Axis Started
1902.555s [INFO - Marlin:10] enqueueing "G28 X I D P"
1902.555s [INFO - Selftest:10] X-Axis home single axis
1902.653s [INFO - Marlin:10] endstops hit: X:-1.76 Y:-3.16
1902.757s [INFO - Marlin:10] endstops hit: X:2.40 Y:-3.16
1902.788s [INFO - Marlin:10] X:180.40 Y:-3.16 Z:4.00 E:0.00 Count X:18040 Y:-316 Z:1600
1902.988s [INFO - Selftest:10] fwd X-Axis u/50 mm/s
1902.988s [INFO - Marlin:10] X:180.40 Y:-3.16 Z:4.00 E:0.00 Count X:18040 Y:-316 Z:1600
1907.004s [INFO - Marlin:10] endstops hit: X:-7.44
1907.054s [INFO - Marlin:10] X:-7.44 Y:-3.16 Z:4.00 E:0.00 Count X:-744 Y:-316 Z:1600
1907.054s [INFO - Selftest:10] X-Axis measured length = 188.239990mm out in range <182.000000,192.000000>
1907.088s [INFO - Selftest:10] rew X-Axis u/50 mm/s
1907.088s [INFO - Marlin:10] X:-7.44 Y:-3.16 Z:4.00 E:0.00 Count X:-744 Y:-316 Z:1600
1911.104s [INFO - Marlin:10] endstops hit: X:180.40
1911.154s [INFO - Marlin:10] X:180.40 Y:-3.16 Z:4.00 E:0.00 Count X:18040 Y:-316 Z:1600
1911.154s [ERROR - Selftest:10] X-Axis measured length = 193.279999mm out of range <182.000000,192.000000>
I I've tried loosening/tightening the belt, using the belt tuner app, but I can only get the X-Axis measured length to vary by tiny amounts.
487.468s [ERROR - Selftest:10] X-Axis measured length = 193.429993mm out of range <182.000000,192.000000>
1070.794s [ERROR - Selftest:10] X-Axis measured length = 193.279999mm out of range <182.000000,192.000000>
1574.927s [ERROR - Selftest:10] X-Axis measured length = 193.289993mm out of range <182.000000,192.000000>
1911.154s [ERROR - Selftest:10] X-Axis measured length = 193.279999mm out of range <182.000000,192.000000>
Can anyone advise what I'm missing? Thanks in advance.
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