Neptune 4 Plus TL4974 and Neptune 4 Max TL4976 - Printer does not power on – Jaycar Electronics

Issue

The printer has been connected to power, but does not turn on.

Troubleshooting

Before doing any work on the printer, turn off the printer power and unplug the power cord.

1.Confirm that you have set the correct voltage;

*The switch position is deep, please refer to the video below to find it.
https://drive.google.com/file/d/1nTaZ-mUXGNDhBkZwEdoF0dLFfD1j6mH4/view?usp=drive_link

2.If the switch indicator light does not light up when you reconnect the power, please check whether the fuse is damaged. The specification of the fuse is AC 250V /10A. You can buy a new one and install it to see if it returns to normal. The area marked in the picture can be disassembled once you disconnect the power cord again.

3.Please try to unplug the USB flash drive and then turn on the printer. Can the touch screen light up? If the touch screen still does not light up, turn off the printer's power. Check whether the three wire plugs on the back of the touch screen are loose and try to unplug and reconnect the three plugs.

If it still does not turn on after reconnecting power, disconnect the power cord again. Refer to the pics below, to open the cover and refer to the accessories to open the cover, then turn it on, and check whether the main board and the power indicator light are on.

Open the lid as follows:

Before removing the bottom cover, unplug the plug at the marked location ↓

4.Turn on the power and check whether the indicator light of the main board is on.

5.Check to see if the light at the marked location is on.