Panasonic TC-P50S60 Technical Manual page 68

SOS Detect Circuit Explanation (14)
These conditions can cause the TV to shutdown and the power LED to blink 12 times
1. Speaker
2. A board (mainly sound processor)
3． Wrong diagnostic by the A board
Speaker L
Speaker R
WOOFER
The IC4900 and IC4901 detect over current of amplifier output and high temperature of chip.
If these chips detect abnormal error, these output the error signal (PROT_N / PROTN) which is open
drain type. When the IC8000 detects low level in AF22, it occurs to shutdown TV and to blink 12 times
for power LED.
12 Blinks Error Code
A12
1
IC4900
2
(YDA174)
3
Audio DSP Amp
4
Woofer audio data
I2S
IC4901
5
(YDA176)
6
Audio Amp
PROT_N
21 AF22
I2C
AH10
AH11
Audio
Data
IC8000
PARAGON
18
PROTN
A
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