Hi Anthony. Welcome to justanswer.
Can you tell me if the led on the adapter of the Canon printer is glowing or not?
Try changing the ports and check. And if you are using any surge protector then connect the plug directly to the plug and try.
The power is not being supplied to your printer. You should try replacing the battery extension or check the voltage at the end of the battery extension port if it is supplying proper voltage or not.
Use without the surge protection
If it is still not working, then check the voltage at the extension cable's end port which is connected to the printer.
Most probably the extension cable is faulty. Call a technician and get the voltage checked.
If the fault is with the power supply board then the circuit will be changed and it will cost you around £40.
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