White screen on Boot

[batsam]

I started getting white screen on boot. to make it turn on normally I'll need to disconnect battery a power adapter for 5-10 min.
already tried factory reset. not working
I want to try original firmware since I installed the custom newer one few months ago. how do I revert to that
I'm open to other ideas/fixes if they don't require disassembly.
thanks

[Redrum]

If it hangs on the white screen forever, maybe try a new power supply? It seems that you have a battery, you could try booting on just the battery, but the battery depends on the power supply for charging, so nothing is guaranteed.

when you mention the "custom" firmware, do you mean the community firmware?

when the radio boots, the logo appears on the screen and the intro sound starts (kind of a crescendo) . Shortly after there is an audible "click" through the speaker. This is when the power amp and other circuitry turn on, and there is a significant increase in current consumption. Does it white screen about there? I had a radio with a bad ps that would click, then reboot, click reboot, etc and it always happened at this point. My assumption was the increase in current demand caused the weak ps voltage to drop. In my case it dropped into a reset, yours could be that it drops into an "unstable" zone (between operating and reset).

Jim

[batsam]

yes I meant the community firmrware.
white screen will appear as soon as display powers on (not afer the sound or the crescendo). but if I turn off the unit for few minutes and power it up again then it boots normal and as long as it stays on the display works normally.

[Redrum]

can you try another power supply? They are relatively inexpensive, and due to age, they either have failed, or will fail.

If you are in the US, I bought one of these and they work fine:

https://www.ebay.com/itm/162185304350

Regarding the community firmware, I don't use it, but I believe all you need to do is go to the LMS setting, plugin tab, and uncheck community firmware, restart LMS. Perhaps someone else can confirm or correct me, I have not done it.

Jim

[batsam]

I'm not in the u.s
however it does that even when powered on battery alone

[Redrum]

understand, but, as I mentioned, are you sure the ps is properly charging the battery? If you can get it to boot normally, is it always in the "charging" state, or does the icon read the full state?

when you are disconnecting all power for a set time, you are allowing all of the capacitance to discharge. Without this time, it is possible this capacitance is not allowing the voltage to a component (say the microprocessors, ASIC, SOC, etc) to enter a reset state, but time does allow the slow discharge to reset.

Most micros want to work above, say Y volts, and will reset if the voltage drops below W, but X, which is in between is an unstable/unpredictable range. I am guessing (only guessing) your radio might be in that range, locked up, and allowing the time, allows it to reset.

Example (just an example) - some 5v systems, will operate above, say 3.3v, and reset below 0.7v. 0.8 - 3.2v, the system should never be in it, but some components may work, may not, maybe sort of work.

Your description sounds like power to me, that's all. Especially because of your description of needing to discharge. You could try this to verify. With battery out, get to white screen, unplug adaptor, short the pin and barrel of the power jack on the radio, restore power with supply, turn it on. If it restores like your wait does, that's what's happening.

Jim

[batsam]

"when you are disconnecting all power for a set time, you are allowing all of the capacitance to discharge. Without this time, it is possible this capacitance is not allowing the voltage to a component (say the microprocessors, ASIC, SOC, etc) to enter a reset state, but time does allow the slow discharge to reset."

in this case will a new power supply fix that

If I remeber correct the battery is always in charging state but I need to check
p.s I am no longer disconnecting the ps, it seems that turning the unite off for 1 minute (ps connected, battery disconnected) will make it boot correctly

if the battery is connected the above method might not work or need more time off .....not sure.
if I repeat that method below 50 sec off it will boot with white screen.

offcicial firmware restore did not fix the problem either

[Redrum]

I am unsure of the mechanisms of the battery charge/supply. It could be that the battery is behaving as I describe "capacitance". After all, capacitance is charge storage, so is a battery.

It's interesting that with just the PS you can recover more quickly.

I hate to steer you wrong. I seem to always be pushing new power supplies to fix odd behaviour that no one else is seeing. It's possible you have an issue with the radio. But this is how the cheap switching supplies fail with age. Remember, unless your radio was in storage, they are "on" 24/7 for over a decade. The failure mechanism is you can measure the voltage (in this case 18v) not plugged in, but as soon as it's loaded (current is drawn), the voltage droops. If it droops far enough to be in the unstable zone, you get these lockups.

This is why it's often the solution to "all of a sudden" problems.

Good luck;
Jim

[batsam]

Ok thanks. I'll consider buying a new ps

[joys_33]

I'm afraid that this error appears regardless of the source, it's a feature of that display, they just don't work as they should.
The problem is that new displays are almost impossible to find, but apparently the display from the Logitech g19 keyboard should fit, but they are also almost unobtainable, or they have the same problem with the display.