How long have you had the set for, and when did the problem occur?
Was it after a storm or power outage?
Does the standby/timer light blink continuously, or in a pattern (such as 5 blinks, pause, 5 blinks, pause, etc.)?
Please disconnect the set from AC power, then press and hold the power button on the TV itself (not the remote), for 10 seconds. After another minute, plug the set back in and press power once. Do you still have the same problem?
The 3 blink code on this set indicates that either the lamp is not seated properly (has become loose), or the lamp cover is open (or the switch is not engaged). Please pull the lamp and re install making sure it is secure. Then additionally make sure the lamp door is closed tightly and securely. Power on the set and let me know if you have the same problem.
Then the problem is that the Lamp sensor switch or the lamp door sensor switch have failed. They are both wired together in series, and either one of them failing will cause the symptoms you're having on the TV- not allowing it to power up and causing the 3 blink code you're getting. There are no buttons you can press or resets that will fix the problem and you will have to have the switches checked out and replaced as necessary. The average cost for this type of repair is around $125 parts and labor. You can use the link below to locate a tech in your area:
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