PDP-505PE
70
1234
1234
C
D
F
A
B
E
7.1.8  TROUBLESHOOTING
Symptom Defective Assy Possible Cause Check Point
Possible 
Defective Part
Remarks
No power (both red and green LEDs unlit) Cable disconnection CN4001
Check if the connection between the POWER SUPPLY and PANEL 
IF assemblies is properly made.
No power (green LED not lit) Defective 114-pin FPC CN4004 - CN5001 ADY1081 Check if the FPC is broken or not securely inserted.
The power is (sometimes) interrupted. Defective system cables CN4002, CN4003
Check if the system cables are securely connected. (See "7.1.4 
Operation when the Media Receiver is not connected.")
The power is interrupted, and the red and 
green warning indications appear on the 
screen.
While the red LED remains lit, the green 
LED begins flashing (200 ms).
System cables not connected
No backup copy
Check connection of the system cables. (See "7.1.4 Operation 
when the Media Receiver is not connected.")
Key input not effective
Cable disconnection CN4801 - CN4851 ADD1225
Check if the FPCs are properly connected. Check if imparting 
vibration to the unit affects key inputs. Check if a pulse is output 
when the key corresponding to Pin 2 of the CN4852 is pressed.
The backup copy process was not performed when the Digital Assy 
was replaced. (See "7.1.7 Backup when the main unit is adjusted".)
Cable disconnection CN4852 - CN4010
Check if the cables are disconnected or not securely connected. 
Check if a pulse is output when the key corresponding to Pin 8 of 
the CN4010 is pressed.
KEY CONTROL Defective KEY SCAN IC KEY CONTROL Assy IC4851
Check if a pulse is output when the key corresponding to Pin 2 of 
the CN4852 is pressed.
Remote control unit not effective
Cable disconnection CN4901 - CN4010 Check if the cables are not connected or securely connected.
PANEL IR Defective infrared receiver PANEL IR U4901
Check if a pulse is output when the key corresponding to Pin 3 of 
the CN4010 is pressed.
Abnormality in a one-eighth area of the 
screen
DIGITAL VIDEO Defective IC4 IC4 BLOCK IC5401
Check if an abnormal area in the screen changes when the FPC 
connected to the address corresponding to the abnormal area is 
replaced with the one corresponding to the next address.
ADDRESS
Check that an abnormal area in the screen does not change when 
the FPC connected to the address corresponding to the abnormal 
area is replaced with the one corresponding to the next address.
Abnormal screen
(Data of every other dot are abnormal)
Defective 114-pin FPC CN4004 - CN5001 ADY1081 Check if the FPC is broken or not securely inserted.
[ Diagnosis of abnormalities other than shutdown and power-down ]