Power supply board led green light blinks 3 times.

1. Open internal fuse
2. Power supply failure

...and?

E5 means cartridges error - to fix press the "stop\reset" button for 5-7 seconds and then release it.

You can also try this:

1) With the printer power turned off but connected to a power source, while pressing the Resume/Cancel button, press and hold the Power button.
(DO NOT release the buttons. The Power LED lights in green to indicate that a function is selectable.)

2) While holding the Power button, release the Resume/Cancel button. (DO NOT release the Power button.)

3) While holding the Power button, press the Resume/Cancel button 2 times, and then release both the Power and
Resume/Cancel buttons. (Each time the Resume/Cancel button is pressed, the Alarm and Power LEDs light
alternately, Alarm in orange and Power in green, starting with Alarm LED.)

4) When the Power LED lights in green, press the Resume/Cancel button the specified number of time(s)according to the function listed in the table below. (Each time the Resume/Cancel button is pressed, the Alarm and
Power LEDs light alternately, Alarm in orange and Power in green, starting with Alarm LED.)

4 times----Green (Power)------Waste ink counter resetting

Hi, this is main board failure and you will need to replace this vital board. you power board is fine but, it is unable to send a proper current through the main mother board due to the damage at hand.

clicking = power supply not coming up
bad power supply, or bad (shorted) part causing power supply to not come up
with a volt meter we can troubleshoot

Those blinks [flashes] are fault indication (Error Codes). From the number of blinks occur at one time switch ON, you can get an idea about the faulty circuit section inside it. This will make repair easy. These are called blinking codes. Make sure about the exact number of blinking of the standby/power LED, by switching On & OFF the set, for at least two times. Count it carefully. If you wish to get some details, check the site linked here. It has details about blinking codes, and fault locating procedure, to many popular brand TVs and other devices.
http://homenol.blogspot.com/
http://electronicshelponline.blogspot.com/
If blinks continue without any pause, the main board is faulty.

Those blinks [flashes] are fault indication (Error Codes). From the number of blinks occur at one time switch ON, you can get an idea about the faulty circuit section inside it. This will make repair easy. These are called blinking codes. Make sure about the exact number of blinking of the standby/power LED, by switching On & OFF the set, for at least two times. Count it carefully. If you wish to get some details, check the site linked here. It has details about blinking codes, and fault locating procedure, to many popular brand TVs and other devices.
http://electro-medical.blogspot.com/
http://homenol.blogspot.com/
http://electronicshelponline.blogspot.com/
If blinks continue without any pause, the main board is faulty.

You have a 8.6v supply error according to the 7 error code being displayed, what you can try is when the set goes to blinking disconnect the Y sustain board (if looking at the tv from the back the board on the left) from the upper left side of the power supply, if the error code stops then you know your Y sustain board is pulling down your power supply and causing the error, if the error code continues you have a probelm with your Logic Board (located under your Small Signal Board) disconnect this from the Y sustain board and see if the error code stops if it does you know that the Logic board is bad, if the error code is still blinking then the 8.6v supply line from the Power supply is faulty and the Power Supply needs to be replaced

The fuse is on the power supplu board, but dont think thats your problem. Is the setompletely dead when you try to power it up? Does the LED light blink? If so how many times does it blin before it pauses for a second.

How many times does the POWER led blink per sec? (dont worry about the OPC)

2x = power supply (not as expensive to fix)
3x = Main board (expensive to fix)