LG 26LG40-UA odd menu problem (possessed)

[Toasty]

Complaint of menu coming up on screen and random switching of functions. Unit will also turn itself on at random. Random menu can not be turned off by remote "menu" button or any controls. Turning unit off and back on by remote or manual power button does not clear problem. Unplugging unit does.

Came into shop without the symptom and ran 2 days with no problems. Customer had unplugged unit 2 months prior and used another set. I was unable to duplicate problem. Returned unit to customer.

Tonight they called saying it was doing it again. It has been 7 days since its return and has been plugged in that long. It was running fine all day and then it started again. Unplugged set for a few minutes and problem cleared. Was fine as of 2 hours ago.

Any ideas what is going on?

Toast

[Toasty]

Re: LG 26LG40-UA odd menu problem (possessed)

Unable to upload owner and service manuals. Both PDF's, both around 5.5 meg...?

Let's try this another way until TC can figure it out:

Owner's Manual

Service Manual

There!

[PCBONEZ]

Re: LG 26LG40-UA odd menu problem (possessed)

I start by doing an extra thorough visual inspection focusing on cold solder joints, crimped wires and bad connector pins.
.
I know, you knew that.
Some days a body just doesn't feel like doing the simple sh*t.
It's boring!
.

[PlainBill]

Re: LG 26LG40-UA odd menu problem (possessed)

Make sure you're at the latest firmware level. This COULD be some sort of overrun error. Scope the signal from the IR receiver to the interface chip. As PCBONEZ suggested, check for suspicious solder joints.

PlainBill

[kc8adu]

Re: LG 26LG40-UA odd menu problem (possessed)

crud on the button board?
windex,spills,ect.
or noise/ripple on supplies.

[Wizard]

Re: LG 26LG40-UA odd menu problem (possessed)

Change all the switches or replace the buttons board.

RCA was infamous for this years ago, more worse with smoker.

Cheers, Wizard

[tmwalsh]

Re: LG 26LG40-UA odd menu problem (possessed)

I'd bet on spikes in the power supply, or bad connections causing the microcontroller go go nuts. The menu showing up is the sort of thing that one would expect when the thing was reset to its factory state after losing power.
tom

[Toasty]

Re: LG 26LG40-UA odd menu problem (possessed)

Update:

I have not seen the unit again. The customer unplugged it for a minute and plugged it back in. No problems since. I do not know if I will see it again, if they can correct the issue that quickly and easily.

It would also be a bitch to try and find a problem that is that intermittent. Leave it running on the bench for a week... not!

I did ask them to run their fingers across all of the control buttons on the side of the TV the next time it happens. If it clears, then that would be the place to start. If not, well.....

I'll update if I ever see the unit again.

Thanks to everyone for the input!

Toast

[Toasty]

Re: LG 26LG40-UA odd menu problem (possessed)

Upload of PDF manuals again. Had to do it from my site.

Above off-site links are no longer valid. Files deleted.

.