Read LG 42PM4M-WA (CHASSIS:PM75A) Service Manual online
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TROUBLE SHOOTING GUIDE
15. HDMI mode
Is only video
normal?
Is only audio
normal?
No
Yes
Download EDID data each port.
Check the TMDS line wave.
(R312~E3273)
(R312~E3273)
1. Check the HDMI receiver’s status register. (0x60, offset 0x06)
- If the value is 0xf or 0x8, it is normal.
2. Check the HDCP register. (0x60, offset 0x06)
- Enable bit 6 : HDCP key loaded
- Enable bit 5 : HDCP decryption active
- Enable bit 4 : HDCP authentication attempted
- Enable bit 5 : HDCP decryption active
- Enable bit 4 : HDCP authentication attempted
Reset TMDS power down/ on register.
- 0x60, offset 0x3f : 0xf7 => 0xff
- 0x60, offset 0x3f : 0xf7 => 0xff
Check HDMI source.
Change to another source or cable.
Change to another source or cable.
Yes
Is the wave
continuous?
Normal video,
Normal audio?
No
Yes
Replace the IC508.
No
1. Unplug and plug in the HDMI cable.
(sometimes ESD surge occurred at HDMI port.)
2. Check the HDMI Mute register. (0x68, offset 0x37)
3. Check the Audio-out channel mute register (0x68,
3. Check the Audio-out channel mute register (0x68,
offset 0x32) is appropriately enabled.
Yes
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