Turns on and off immediately

Turn Lamps
With the ignition switch in the RUN position, battery positive voltage (B+) is supplied from the IP fuse block T/SIG/BU LP/BTSI fuse 1B via CKT 539 (PNK) through the turn signal flasher to the normally closed switch in the turn/hazard switch via CKT 16 (PPL). With the turn switch in the left turn position, battery positive voltage (B+) is applied through the turn switch and two paths to the turn lamps. One path is to the left front park/turn lamps and the side marker lamps via CKT 14 (LT BLU). The second path is supplied to the left tail/stop/turn lamps via CKT 18 (YEL). The lamps go on immediately. The lights begin to flash when the current heats up the timing element in the flasher, and the flasher repeatedly opens and closes the circuit. A similar procedure is followed when the turn switch is in the right turn position. Battery positive voltage (B+) is supplied to the right front park/turn lamps and the side marker lamps via CKT 15 (DK BLU). Battery positive voltage (B+) is supplied to the right tail/stop/turn lamps via CKT 19 (DK GRN).
Hazard Lamps
Battery positive voltage (B+) is supplied at all times from the IP fuse block BRK/HZRD LPS fuse 6B via 140 (ORN). The current flows through the hazard flasher to the normally open switch in the turn/hazard switch. With the hazard switch in the ON position, battery positive voltage (B+) is applied through the turn/hazard switch to all four paths used by the left and right turn lamps. The following components flash on and off:
• All turn lamps
• Both indicators
With the hazard switch in the ON position, the turn circuit is always open, and the hazard flasher controls the lamps.

I was reading the troubleshooting guide and used your symptoms to find this information. In the following case, power off the monitor immediately and contact your dealer or authorized Service Center. The monitor turns off 5 seconds after powering on and then the POWER/STANDBY indicator blinks. It indicates that the power supply circuit, plasma display panel, temperature sensor, or one or more fans have been damaged. It is very common for these TVs to get filled up with dust. The dust covers and insulates internal components and cause them to over heat. I hope this helps. Good Luck.

I really don't think you would have a fuse problem . You should hope not anyway , fuse's don't go bad or blow for no reason . A blown fuse would be caused by a direct short to ground on a battery power supply circuit , high current draw . I would look at the flasher or switch as probable cause . Viewing a wiring diagram an testing the electrical circuits is the best way to find the problem . Turn Lamps
With the ignition switch in the RUN position, battery positive voltage (B+) is supplied from the IP fuse block T/SIG/BU LP/BTSI fuse 1B via CKT 539 (PNK) through the turn signal flasher to the normally closed switch in the turn/hazard switch via CKT 16 (PPL). With the turn switch in the left turn position, battery positive voltage (B+) is applied through the turn switch and two paths to the turn lamps. One path is to the left front park/turn lamps and the side marker lamps via CKT 14 (LT BLU). The second path is supplied to the left tail/stop/turn lamps via CKT 18 (YEL). The lamps go on immediately. The lights begin to flash when the current heats up the timing element in the flasher, and the flasher repeatedly opens and closes the circuit. A similar procedure is followed when the turn switch is in the right turn position. Battery positive voltage (B+) is supplied to the right front park/turn lamps and the side marker lamps via CKT 15 (DK BLU). Battery positive voltage (B+) is supplied to the right tail/stop/turn lamps via CKT 19 (DK GRN).

http://www.bbbind.com/free-tsb

Return it immediately.

I have an LG as well.
My troublshooing says:
"Check the power control setting.The power supply may be interupted.
Check if the Auto sleep feature is actiated in the Time settings.
Refer to the " Sleep timer".
If there is no signal while the TV is on, the TV will turn off automatically after 15 miutes or so"

Hi, The TV is shutting down because there is an internal fault, there is more likely a panel that needs replacing or a few faulty components.

It's more than likely repairable.

If it's under warranty contact your dealer for repair or replacement.

on/off sensor/switch went out

Sounds power supply board is bad in your TV and most probably replacement of all electrolytic capacitors in power supply board will solve the issue.
Take TV to local TV repair shop for repair.
Thanks.

We had a bad storm and lots of lightening. After that my tv (which is plugged into a surge protector) would turn on and then immediately turn off. I unplugged the TV from the surge protector and plugged it into a different outlet and it works now.

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