Display won't turn on + blinking red light

Hi @electricleaf,

You said "...I even tried the test where you unplug the motherboard and see if backlights turn on..." so did the backlights turn on, you didn't say?

Have you measured the voltages on the power board on cable connector CNM803 to check if they are as described in the table printed on the board close to the connector?

Where were you told the problem would be on the board in the image you posted besides the fact that it is the power board? There's nothing really obviously visually wrong with the board i.e. no burnt out or heat stressed components etc. Although this doesn't mean that it is OK

The backlights did not turn on. I wasn't sure where to look so I turned off my lights so my room was pitch black anyways and I didn't see any lights. I have not measured any voltages, which I assume is using my multimeter. The issue is my multimeter works on all settings, but then the display just shuts off when I set it to diode check mode. Could you maybe help me with how I should measure voltages? Electrical testing is new to me!

@electricleaf

If it is new to you then be very careful as there is exposed LETHAL AC voltage on the power board when the power is connected. Watch out what you touch and where you place your fingers/hands etc

You need to set the DMM to Volts DC 20V range and then place the black lead (connected to the Com in the meter) on a screw head as this is an earth point. The red lead (in the V socket of the meter) should be used to touch on the connector pins of the connector.

BE CAREFUL - do not short out the pins with the meter test probe - carefully place the probe on 1 pin only and check what the measurement is.

You may not be able to get to the even numbered pins as only the odd numbered on exposed at the top of the board but at least it may give an indication of what's happening withthe power board.

If the DMM has a user manual (or one can be downloaded) I highly recommend that you read it first to understand how to operate the meter.

Just to clarify, I will want to plug in the tv, then touch the black prong to a screw for a ground, and then the red to each individual pin on the connector, and I assume the pins are the metals parts that are directly to the left of the table?

@electricleaf

Yes.

Touch and hold the black prong as the earth must be connected all the time for the meter to work when you touch the red to the different pins.