Thread: M2-ATX +5V and +3,3V dead?

Im not sure what you think u are doing but u obviously have some issues in your wiring setup look at the attached image for a guide on the voltage rails. Where are you getting your M2 PSUs from?

I am working in my daily life as an electrician, so I have a little clue about what I am doing, but there isn't any +5Vdc in the molex connector. neither +3,3V or +5vdc in the atx 20 pin conector..

Originally Posted by Lasse Poulsen

Hello..

I have a M2-ATX plugged into my micro-atx motherboard with 2600+ amd sempron cpu, 512mb ram, 120gb ide harddrive and the M2-atx is powering my touchscreen too.. Nothing else.

I plugged it into the car and powered on.. Worked fine, when I was driving the next day, the computer shut down after ~10min, and wouldn't power up again.. The harddisk made funny noises, like powering up and loosing power, I then tried to remove the power from the harddisk, and the computer powered up fine.

So I took the computer inside and put +12V on the m2-atx from a standard computer psu (~400W), and the computer powered just fine. I then put the carpc back into the car, and nothing happened when I powered it up. I then tried to measure the volts;

I have then later tried to measure the +3,3V, but that's dead too.

I measured the total power usage of the m2-atx to 7amps, on the input.
It went to around 15Amps shortly on startup.

There is no components that look burned, or smell burned.

My question then is, is this a simple problem? Or can I consider the M2-atx as dead?

This is my third M2-ATX, I had two before that burned a component (Others have had that problem in here)

Between yellow and black=+12,32V
Between Red and yellow=+12,32V (Should be +7V??) Dude red wire is 5 volts! yellow is 12 Volts
Between Red and black=0v

What are u using to measure? And How are u getting a Current(I Amp) readings are you using a bench supply or a DMM to get the data.

Originally Posted by Lasse Poulsen

I am working in my daily life as an electrician, so I have a little clue about what I am doing, but there isn't any +5Vdc in the molex connector. neither +3,3V or +5vdc in the atx 20 pin conector..

which molex connector?
Do you have the pin 14 grounded to turn on the PSU ON pin? This turns on the voltage rails.

I am using a Multimeter to measure the voltages and current amps.

In the 4 pin molex connector I can only measure the voltages above.
And yes, the pin 14 is grounded, since there is +12V in the 4 pin molex connector.

You should not use the multimeter to measure the amps it can add a load to the supply thus making your m2 atx crowbar becuase you probably have the Multimeter set to what current limit 10 amps? The m2atx is probably current limiting on that rail that you are checking. is the inductors (big square parts) getting warm?

The multimeter is not making a great load.. Probably something like 0,1-0,5amps at max.. And the multimeter was at the input of the m2-atx..

And the 2 inductors where warm.. and the others wasn't.. And now there isn't any +5v

Maybe it's me, but llowing current to pass from +12v to +5v would be bad, woudl it not?

what?

I have measured the current from the INPUT side of the m2-atx.. no current limiting, no extra load on m2-atx..

On the OUTPUT side I have only measured the voltages, which isn't there, on other than +12V