Don't run a morbark, but my bandit runs a L.O.R. Tachometer.
According to my manual, yours may be a
L.O.R. MFG
PART NUMBER 900-2906-82L
For service call 1-866-644-8622
I don't have any input on the error codes. But like Brendon said, check your wires and harnesses. Look for wear, loose...