To be honest you are going to need a circuit diagram which I know can be difficult to get hold of from a lot of manufacturers. Also at least a decent multimeter. Otherwise its partly like working blindfold unless your very lucky finding the fault without either one. Good luck anyway.
I don't want you to waste money ie yes the psu may be at fault however it may be additional parts of the cicuit that are causing the psu to malfunction. If you can isolate the psu completely and test this individually then this is a start at least. As I say fault finding without a circuit diagram and relative test equipment is difficult and a hit and miss. Believe me this used to be my profession and I know how difficult and time consuming this can be.
I thought I would take a look in my tm F3/5
And it was the same power supply
The psu out of the 5402 m3 that had me baffled I had actually fixed after all
It was just a couple of caps that had gone
Tested on the f3/5 all good
The only problem is that I cannot get any life out of the 5402 m3 with either psu
Any ideas
Thanks for your help Aerosmith William and Manic
I did send Technomate an email the other day, still waiting