I'm troubleshooting a finicky Maytag Bravos HE top-loading washer (model MVWX550XW1), and seem to be at a standstill as I'm receiving intermittent symptoms, and progressing through the service manual steps is proving inconclusive...
The error codes are F7 E1 (basket speed sensor fault), and F7 E7 (motor unable to reach target RPM).
Here are the symptoms:
Over the past few months, we've had a few cases where the machine gets stuck with a flashing lid lock, even when "off", and won't do anything until it times out several minutes later. It has also had a few cases of disappointing washing performance, although I'm not sure if that is a failure symptom or a characteristic of the HE design...
Today it had a new, more pressing issue - we were washing a small load of some seasonal clothes that had been packed for a while, so a few of the items were t-shirts and the like that were folded. The washer ran its cycles and competed, and when my wife opened the lid, the lower items were soggy wet, a few items on top still had dry parts (had never touched water), and the wet t-shirts were still folded. So although it took the normal amount of time, it might not have agitated or spun...
Following through the steps in the service manual, it would seem like everything checks out after doing the functional checks. I can lock/unlock the lid repeatedly without issue, the fill valves check out, etc, etc. The manual tachometer test is successful as well. The machine agitates, and it can spin as well without any unusual sounds or noises. The tub spins freely by hand, and selecting spin & drain spins and drains as expected.
What happens though - I ran the automated test set, and the first time through, it seemed like it stopped the spin test very quickly - only running the motor for a half-second or less, then skipped right past the 30-45-second spin down and went straight to the "lid will unlock" step where it stalled for several minutes with the flashing lid lock light, for long after the tub had come to a stop.
However, what is strange is that I cleared the codes and re-ran the automated test set, and this time when it got to the spin stage, it spun up to full speed and for the expected time, but then immediately skipped to the "Done" stage, played the chime, and unlatched the lid... all while the tub was still spinning at nearly full speed. After this second test, there were NO fault codes stored.
It *seems* like an intermittent speed reading... but like I said, that function checks out when doing the manual tests.
Before I fire the parts cannon at this, does anyone recognize this behavior as a common intermittent failure mode?
Thanks in advance.