Head Operation (Up & Down) Is Out Of Order - Sony UP-895 Service Manual

5-4. Head Operation (Up & Down) is Out of Order
START
Does head motor operate?
YES
Are signals from sensor
available at pins 2 and 3 of CN2
on MA-99 board?
YES
5-4
IC400 and Q402 on MA-99 board are defective.
NO
The head position sensors (PH21 and PH22) on SE-531
NO board are defective.
Pins 16 and 17 of IC304 on MA-99 board are defective.
UP-895/(E)