EPC and CEL problem

Hi Guys

I have a strange problem with my fabia 1.4 16v

the electric window in driver side sometimes failed to work so i decided to to look at the switch.

demounted the switch totally in to pieces then tested with ignition on motor not started did several tests and finally i found the reason for the problem fixed it.

assembled all again was then going to start engine to drive out of garage but no power to starter, i then thought okay maybe i used all battery power

charged battery for an hour and now engine starts, But EPC and CEL was lit and engine could not take any rpm.

demounted then both cables from motor control unit and mounted again,

now motor tryes to start but no ignition, demounted cables for motor control again to check that i have mounted them ok nothing found mounted again and now engine starts ok and only CEL was lit

Car runs ok so decided to drive home, then next day when i started the car everything was okay no warning lights strange but after 2 days with no problem CEL is on again but car runs ok.

any one that can explain why messing around with electronic for windows can course this problem.

i am offcourse going to get a read out of the fault codes to see if there is any explanation there

alternative by a faulcode reader my self

what faultcode reader would you guys reccomend

in advance thanks for any answers on this strange problem

Claus V