How do I test this adaptor brick

[embalse]

How can I test whether this is dead or alive, without testing it on another laptop?
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[hornetstinger]

Voltmeter. That won't test under load though

 

[Thekwango]

Multimeter, I’ve a cheapo jobbie I got off Amazon years ago for just such jobs.

 

[embalse]

Voltmeter. That won't test under load though

Do you mean to attach the Voltmeter to the 3-pin import socket?

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[hornetstinger]

No. That's the input. You'll want to connect one prove to inside of the barrel plug and the other probe to the outside of the barrel plug

 

[embalse]

No. That's the input. You'll want to connect one prove to inside of the barrel plug and the other probe to the outside of the barrel plug

Great thanks, I'll get a Multimeter.

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[Bidley]

If you get nothing from the barrel jack, be sure to check continuity from the mains plug to the input plug - unlikely that that would be the culprit, but only takes seconds.

 

[embalse]

If you get nothing from the barrel jack, be sure to check continuity from the mains plug to the input plug - unlikely that that would be the culprit, but only takes seconds.

Yep. Ordered a multimeter and will test the continuity too.

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[embalse]

Ok, I have a multimeter. Hopefully, someone with far more experience can tell me what is going on.
The cables to and from the adaptor have electric current/continuity. I tested the multimeter with a 9v battery (1st image) which is accurate.
I first tried testing the barrel plug in auto mode. It would only test the resistance. (2nd image)
I then put the settings to Voltage only. (3rd image) The image shows a reading of 00.18 but honestly, it had various readings including much much higher, none of them the 20.0v output stated on the adaptor
Is this brick dead or am I not using the meter correctly

 

[embalse]

OK. I have discovered the fault.

When I connect the Cloverleaf socket to the adaptor it blows the mains plug 5A fuse.

So I am guessing there is a problem with the adaptor itself?

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