FAQ
TL;DR: LG 42LB650V boot-logo hang: one test showed 0% improvement after erasing IC103; "We don't need the VCCQ." This FAQ compiles proven thread remedies for technicians tackling this fault. [Elektroda, almou, post #17853473]
Why it matters: It helps bench techs revive LG 42LB650V sets efficiently without defaulting to full board swaps.
Quick Facts
- Model/board context: LG 42LB650V mainboard EAX65384004 (1.5) / EBT63439306; LC/LD LE42B/42G family. [Elektroda, naprawa tv, #17388739]
- Primary remedy flagged: EMCC (eMMC) reflash or replacement to clear boot-logo hang. [Elektroda, rob1, post #17853484]
- If eMMC reads consistently across several dumps, hardware is likely intact; compare files first. [Elektroda, Adewag, post #17402599]
- Read may succeed while write fails; a new preprogrammed eMMC avoids repeat returns. [Elektroda, rob1, post #17402884]
- After programming, verify HDCP keys, internet connectivity, and CAM authorization. [Elektroda, Adewag, post #17402599]
What causes an LG 42LB650V to hang on the boot logo?
Contributors point to corrupted EMCC (eMMC) content causing the boot hang. Reprogramming or replacing the EMCC resolves it in this case. [Elektroda, rob1, post #17853484]
How can I check if the EMCC/eMMC is damaged or just corrupted?
Try multiple reads. If all dumps match, the chip is likely not physically damaged. “If the memory can be read, it should not be damaged.” Then proceed to program and test. [Elektroda, Adewag, post #17402599]
Will erasing or replacing EEPROM IC103 fix the boot loop?
One suggested approach is to replace EEPROM IC103 with a blank and then perform a reset. This is often tried before deeper storage work. [Elektroda, jean0791, post #17388910]
I erased IC103 and nothing changed—what should I try next?
Move to the EMCC path. Program or replace the EMCC with a known-good image to resolve the boot hang. [Elektroda, rob1, post #17853484]
What’s the practical EMCC recovery procedure?
- Read the EMCC; back up if readable.
- Program a new EMCC using a compatible programmer and adapters with a matched image.
- Refit, boot-test, and proceed with functional checks.
The TV may recover, though not all units do. [Elektroda, rob1, post #17404698]
Do I need VCCQ when working on this memory?
One contributor reported VCCQ was not needed in their attempt. Their EEPROM erase yielded no change, reinforcing the EMCC focus. [Elektroda, almou, post #17853473]
Can I block the EEPROM read at boot by forcing SDA to Vcc or GND?
Avoid this. Forcing I2C lines risks damage and is not a supported bypass here. It was discouraged in the discussion. [Elektroda, rob1, post #17439474]
Which tools do I need to program the EMCC/eMMC on this board?
Use an eMMC programmer and the proper adapters. Keep new EMCC chips in stock, as this type appears in many TVs. Prepare a matched image. [Elektroda, rob1, post #17404698]
Why can I read the EMCC but fail to write it?
Writes can fail while reads still work. “The memory is readable, but it may not be writable.” Replace with a preprogrammed new EMCC. [Elektroda, rob1, post #17402884]
What should I test after flashing a donor image?
Verify HDCP keys on HDMI, internet connectivity, and CAM module authorization. Confirm there are no service or pairing issues. [Elektroda, Adewag, post #17402599]
Has anyone confirmed the shared fix works?
Yes. At least 1 confirmation exists in the thread; another member wrote “I confirm” after applying the fix. [Elektroda, Adewag, post #17390087]
Can every unit be revived with EMCC programming?
Not all. One contributor noted, “the TV gets up after that but not all.” Plan for possible mainboard replacement. [Elektroda, rob1, post #17404698]
How do I source a programmed EMCC for this mainboard?
Program a new EMCC using your programmer. Obtain the needed adapters. Keep EMCC devices in stock since they fit many models. [Elektroda, rob1, post #17404698]
What is IC103 on this board?
IC103 refers to the mainboard’s EEPROM used in resets. One suggestion replaces it with a blank before system reset. [Elektroda, jean0791, post #17388910]
.
