Pioneer PRO-141FD Service Manual page 57

5
[5] MAIN ASSY
Flowchart of Failure Analysis for The MAIN Assy
Failure analysis for the
MAIN Assy => MA1
The STB LED does not light although
STB 3.4 V power is supplied.
Does the POWER switch on?
Yes
Is resetting of the Main
microcomputer canceled?
Yes
Is the voltage at Pin 3 of the M11
connector High?
Yes
Is the M11 connector securely
connected?
Yes
Is the cable that is connected to
the M11 connector broken?
No
No problem with the MAIN Assy.
Check the LED Assy.
Failure analysis for the
MAIN Assy => MA2
The RELAY port does not work.
The power is not turned on.
Is the voltage at Pin 50 of the M8
connector 3.4 V?
Yes
Are the voltages (1.8 V/3.4 V)
supplied to the main microcomputer?
Yes
Can the unit be turned on, using
the remote control unit?
Yes
Can the unit be turned on, using
the Power switch on the unit?
Yes
Can the unit be turned on, using
RS-232C commands?
Yes
No problem with the MAIN Assy.
5
6
No
Turn the POWER switch on.
No
Replace the MAIN Assy.
No
Replace the MAIN Assy.
No
Securely connect the M11 connector.
Yes
Replace the cable (J116).
No
Replace the MAIN Assy.
No
Replace the MAIN Assy.
No Replace the cable (J117) that
connects between the IR and
MAIN Assys.
No
Replace the cable (J116) that
connects between the KEY and
MAIN Assys.
No
Replace the 50P cable (J213) that
connects between the I/O and
MAIN Assys.
6
7
Failure in the RST IC (IC7003) output or its peripheral circuits
Failure in the line between the Main microcomputer and M11 connector
Relay control is unable unless it supplies a power supply to the module microcompute.
NG
Replace the IR Assy.
NG
Replace the MAIN Assy.
NG
Replace the KEY Assy.
NG
Replace the MAIN Assy.
NG
Replace the I/O Assy.
NG
Replace the MAIN Assy.
PRO-141FD
7
8
A
B
C
D
E
F
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