Panasonic PT-60LCX64-K Service Manual page 122

PT-60LCX64-K
How to solve the problem indicated by the Error Indication of LED
Error No.
+3.3V line on the Main C.B.A. error.
12)
13) -5V line on the Main C.B.A. error.
14) +6.5V line on the Main C.B.A. error.
15)
The Temperature Sensor (R2821) on the Thermistor 2
C.B.A. on the Lamp House is short or open.
Problem
Check if there is a voltage of approx.
+30V at Pin 6 and 7 of P3401 on the
Main C.B.A. for a moment just after
the power is turned on.
Disconnect the connector cable from
P3401 on the Main C.B.A. and check
the resistance between Pin 6, 7 and
Pin 10 of P3401 on the Main C.B.A.
Check +3.3V voltage line on the
Power C.B.A. Repair if necessary.
(Refer to "CHECKING THE POWER C.B.A.")
Check if there is a voltage of approx.
-5V at Pin 8 of P3401 on the Main
C.B.A. for a moment just after the
power is turned on.
Disconnect the connector cable from
P3401 on the Main C.B.A. and check
the resistance between Pin 8 and
Pin 10 of P3401 on the Main C.B.A.
Check -5V voltage line on the Power
C.B.A.
Repair if necessary.
(Refer to "CHECKING THE POWER
C.B.A.")
Check if there is a voltage of approx.
+6.5V at Pin 5 of P3401 on the Main
C.B.A. for a moment just after the
power is turned on.
Disconnect the connector cable from
P3401 on the Main C.B.A. and check
the resistance between Pin 5 and
Pin 10 of P3401 on the Main C.B.A.
Check +6.5V voltage line on the
Power C.B.A. Repair if necessary.
(Refer to "CHECKING THE POWER C.B.A.")
1. Confirm that all connector cables are connected to the connectors correctly.
2. Check the following Temperature data lines.
Disconnect the P2304 connector on
the LCD Drive C.B.A., and check if
the resistance between Pin 1 and
Pin 2 of P2821 on the Thermistor 2
C.B.A. is 5k ~1M .
Check if the voltage at Pin 2 of
IC6302 on the Main C.B.A. is +0.1V~
+4V (Temperature Data1) and Pin 3
of IC6302 on the Main C.B.A. is
approx. 0V (Temperature Data2).
Check if the voltage at Pin 19 of P5302
on the Main C.B.A. is +0.1V~+4V.
Check the signal line between Pin 19
of P2501 and Pin 2 of P2304 on the
LCD Drive C.B.A.
Repair if necessary.
Replace the 20-pin Cable (Ref. No. 14)
between P5302 on the Main C.B.A.
and P2501 on the LCD Drive C.B.A.
Possible Solution
Check the surrounding parts at Pin
YES
7 of IC6302 on the Main C.B.A.
Repair if necessary.
NO
Short-
Check +3.3V voltage line on the
circuit
Main C.B.A.
Repair if necessary.
No shortcircuit
Check the surrounding parts at Pin
YES
62 of IC6302 on the Main C.B.A.
Repair if necessary.
NO
Short-
Disconnect the Rear Jack C.B.A.,
circuit
and check the resistance between
Pin 8 and Pin 10 of P3401 on the
Main C.B.A.
No shortcircuit Shortcircuit
Check -5V voltage line on the
Main C.B.A.
Repair if necessary.
Check -5V voltage line on the Rear
Jack C.B.A.
Repair if necessary.
Check the surrounding parts at Pin
YES
60 of IC6302 on the Main C.B.A.
Repair if necessary.
NO
Short-
Check +6.5V voltage line on the
circuit
Main C.B.A.
Repair if necessary.
No shortcircuit
Replace the Temperature Sensor
NO
(R2821) on the Thermistor 2 C.B.A.
YES
Check IC6302 and the surrounding
YES
parts on the Main C.B.A.
Repair if necessary.
NO
YES
Check the signal line between Pin 19
of P5302 and Pin 2 of IC6302 and
the surrounding parts on the Main
NO C.B.A.
Repair if necessary.
Still NG
122
No shortcircuit