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eeprom reset doesn't work on P2470HD?

Posted: Sat Nov 04, 2017 3:28 pm
by konstantin
Hello,

I've found your very valuable wiki and forum while searching for an issue with my P2470HD (PC Monitor with TV).
Issue:
Since quite some time I cannot store any modification to e.g the channel list, picture setting for the different input sources, ... Apart from that issue it works quite well.
I tried the code for entering into service mode without success. The service manual for the P2470HD (can be found e.g. here: https://www.electronica-pt.com/esquema/ ... lcd-19801/) specifies: "Power Off" "Info" "Menu" "Mute" "Power On" - which has no effect on my device.
My next idea was to reset the EEPROM. The service manual includes a BOM which lists in total 4 EEPROMs. I've found 3 of them in the service manual in chapter 4.3 (PC VGA no screen) - IC803, chapter 4.4 (DVI no screen) - IC901and chapter 4.5 (HDMI no screen) - IC6001.
This leaves me with the 4th EEPROM which is described in the BOM as " IC-EEPROM;24C1024,1Mbit,128Kx8,SOP,8P,4.".
I guess I found it on the board (see attached pictures) as IC3001. The print on the IC is somewhat hard to read on the photo. It reads
"ATMLH946
2GB 1
9H2274"
Now I tried to reset this EEPROM according to the description within your wiki, i.e. either apply GND or VCC (3,3V) to SDA. For SDA I used the soldering point with the name "SDA_EEP" (see photo).
I tried:
1) GND to SDA for 20 seconds while powering on (switch on 230V supply)
2) VCC to SDA for 20 seconds while powering on (switch on 230V supply)
3) VCC to SDA for 20 seconds while powering on (switch on 230V supply) AND turning on the TV with the remote control
Neither worked....

Currently I'm a bit clueless what to do next. Would you have any idea for me?


thanks for your support
Konstantin

Re: eeprom reset doesn't work on P2470HD?

Posted: Sun Nov 19, 2017 11:38 pm
by RogerEBrown
Did you try factory reset before trying eeprom reset?

Re: eeprom reset doesn't work on P2470HD?

Posted: Mon Nov 20, 2017 5:46 am
by juusso
Can be some of eeprom is bad and needs to be replaced?

Re: eeprom reset doesn't work on P2470HD?

Posted: Mon Nov 20, 2017 8:39 pm
by konstantin
@Roger, yes I tried the factory reset before. It just had no effect that's why I went on to eeprom reset
@juusso, that's perfectly possible. But how would I know? Unsoldering the eeprom would be a not-so-easy task as it is covered by the plastic of the CI interface... Would it be enough just to replace the eeprom without any programming?