avrguru,
The source of this problem is likely in one of two places.
1. The touch panel on the television (up or down button) is either depressed or unintentionally making contact.
2. The problem may reside on the board making contact where it shouldn't be.
I don't have any way of knowing which one is the way to go; that said, until you can control the cursor, I might suggest not going into the service menu and possibly enabling something that will have an ill-effect. Just a friendly thought.
--HDTech
Hi, new here. Would definitely appreciate pointing in the right direction. HL-S5687W powers up fine, but within a minute or two acts up. If I go into 'service mode' quickly after power-on, it shows the different service mode options, but soon it starts racing through them as if you are holding down either the UP or DOWN button. Ignores all front panel buttons, except eventually it might respond to the Power button. No LEDs on front are flashing (like they do if you press a button on the remote), so it's definitely not getting a 'bad' signal from the remote control. If you press a button on the remote, the front LED does flash, but has no effect on the TV's actions. Picture itself seems OK (no light engine problems). Any ideas where to start looking?

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