Goodman MSG-12CRN1N Service Instructions Manual page 23

TROUBLESHOOTING
Resetting of Outdoor Control Board Occurs Often During Operation:
If the power is on and the unit automatically enters into reset mode, the instantaneous voltage of the main chip is less
than 4.5v. Check according to the following procedure:
Resetting of outdoor control board often occurs during operation.
After changing indoor control board, check if the failure is repaired.
After changing indoor fan motor, check if the failure is repaired.
Power supply circuit has problems
Indoor Fan Speed Not Responding Properly
If the indoor fan speed has been unresponsive for over 1 minute:
Is connector connection good?
Is voltage being applied to the fan motor?
Yes
No
Yes
Yes
Yes
Fan motor is defective
Yes
(12k Models Only)
No
Indoor control board
is defective
Repair the
connector
Indoor
control board
is defective
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