Hitachi CMP420V1 Service Manual page 11

SERVICE MODE ACCESS
DIAGNOSIS MODE
DIAGNOSIS MODE
This chassis has a limited self-diagnosis mode. When activated, the microprocessor generates a series
of internal communication checks and outputs the results via OSD, as seen on the table below. Since
it uses the OSD to display the results, any circuit failures which result in a "no display" or "no pic-
ture" condition will not be able to be seen, obviously. ANY operation (volume, channel, menu, input,
etc.) will cause the unit to exit from the Diagnosis mode.
Diagnosis Mode
With unit in standby mode
(turned off), press and hold: >
Codes
Most Recent Failure
Code Problem
H11* Tuner problem
H15 Composite video SW IC problem
H16 Component video SW IC problem
H31 Color Demodulator IC problem
H32 Sync separator IC problem
H33 3D Y/C separator problem
F63 I2C Bus latch problem
* Only with units having a tuner circuit
1 5
Results
Diagnosis
H11: OK
H16: OK
H32: OK
F63 F63 - - -
Can not receive the main signal from antenna
Can not receive picture and audio - can not change input mode
No component picture - can not change input mode
Abnormal color - dark picture
Unsynchronized picture
Abnormal color - dark picture/no picture
Can't store data settings
11
CMP420V1 / CMP420V2 / 42EDT41 (PW1A)
After the unit comes on, continue to hold the
buttons down until the initial OSD goes
away. OSD will then appear indicating that
the DIAGNOSIS MODE is engaged.
H15: OK
H31: OK
H33: OK
- - - - - -
Phenomenon Cause
U101 error
I201 error
I202 error
I501 error
I601 error
I302 error
SDA3/SCL3
latched up