Printer Won't Always Power On

[Jerome]

Printer is an HP 4M. It works fine EXCEPT - it doesn't always power on when the switch is turned on. It's not the switch - I tried another switch - same problem.

Sometimes it will come on, sometimes not. Used a voltmeter and verified that there is power coming through the cord. Even tried different power cords.

Once it is on - it stays on; I can wiggle the power cord where it plugs into the printer receptacle and there is no "cutting out" of the printer.

What might be causing this?

Thanks -

Jerome

[raz]

the next stop would be the low voltage power supply.if there is a problem with this,it can cause this ,or perhaps a loose plug inside going to or from this board.as long as that at the times that it does not turn on ,there is no movement at all;like motors or fans running.if there is an overflow of current there,the crowbar circuit will shut down the printer automatically by cutting the power.

[Jerome]

Raz,

Thanks for your suggestion. When it doesn't power on, absolutely nothing happens.

Jerome

[Jerome]

Raz,

Hopefully you will read this. I just tried to turn on the printer. The little lights atop the printer flashed very quickly, then went out and nothing else happened. I waited a few minutes, tried again - and the printer came on perfectly and printed some things for me.

This is puzzling.

Jerome

[raz]

generally,this type of thing would be tied in with the low voltage power supply,though on this printer,the ac and dc /high voltage power supply is tied in on one board.i have'nt looked it up,but it may not be cheap.it may be that the power supply board has a faulty connection of some sort or that it is going in and out.you mentioned a voltmeter/multimeter before.you may be able to check the board in more detail(following the general safety guidlines with using a multimeter).if you have anything connected between the power cord and wall;like a power strip or an uninteruptable power supply,try to bypass it and plug it in directly.or even try a different outlet.you could try opening the printer up and remove and reseat any plugs to the power supply and dc controller,though if you have'nt done this before,it is not very simple,at least not without a manual.if it printed a few things ok the last time it came on ,and the toner was fused ok ,at least it shows that the fuser is getting proper power from the low voltage power supply.(when the power comes in from the wall,the low voltage power supply picks it up and has a direct line to the fuser and the rest goes to the dc controller and is distributed from there).in any case,if it is working for now,wait and see what it does.

[Jerome]

Raz,

Thanks VERY much for your suggestions.

Jerry