Hyundai H-MS1107, Service Manual

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Page 13
Maintenance procedure for the VF part is as follows:
NO
Check if there is any cracking or
short-circuit.
YES
Check if there is any cracking or
short-circuit in the VF output circuit.
NO
NO
NO
NO
YES
YES
YES
YES
Check the power supply of the
decoding board. There are two
voltages: one +5V voltage for
decoding; a3.3V voltage for
servo.
Directly use the VF line to touch the
decoding board to check if the VF
AV3168 output is normal or not.
Check if the voltage of the power board is
normal or not. If there is no voltage, then
check the power supply part.
Check if the 27MHz crystal oscillator
on the decoding board is oscillating
(see the attached figure 6).
Replace it with a crystal oscillator of the
same model or a 27P ceramic capacitor.
Replace it with an Sphe8200a of the
same model.
Replace it with an SDRAM or FLASH of
the same model.
Check if there is any image output
or not.
Directly use the VF line to touch the
front end of the VF output seat of the
power board to check if it is normal
or not (see the attached figure 5).
NO
YES
Check if the Sphe8200a is working
normally or not.
Check if the SDRAM or FLASH is
working normally or not (in
comparison with a normal machine).