At one point my EIII was totally dead. The power supply stopped functioning.
The Power Supply was made by Power-One
http://www.power-one.com/, type SPL150-S109. But they have dropped all support for the SPL150-series and refused to provide me details about the power supply.
This is what the technical manual has to say about the power supply: EIII uses a switching power supply. We do not repair these supplies at the factory and do not even have schematics for them.
A technician helped fixing it but we were unable to trace a component, which looks like a transistor and might even be one, labelled Motorola 21407 8835 K. So if anyone knows what this is, please leave a comment.
I was lucky enough to find a second hand EIII power supply, not cheap though, and now my EIII is back up and running.
Here are the voltages from the power supply as described in the technical manual:
Green wire = ground
Orange wire = +12V
Yellow wire = +5V
Black wire = -14.25V to -15.75V
Red wire = +14.25V to +15.75V
Attached is a photo of the internal power cable. As you can see there's also a blue cable which is not described in the technical manual. I can tell that this is also a ground wire.
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