Ferm One electric screwdriver has no power

[Antti]

Hello!

My friends screwdriver got water inside and stopped working.
He loves it so much that it needs to be repaired.

If anyone has any idea where and what I could measure it would be really helpfull. Motor works fine.

here is some pictures

[Antti]

Re: Ferm One electric screwdriver has no power

heres the pics inside the screwdriver

[megaraider]

Re: Ferm One electric screwdriver has no power

[Probably you posted this in the wrong place... ]

More details needed... but start by:
look for water damages: corrosion, open/shorted connections;
measure battery and see if it charges when connected;
test the power switch;
I don't think the water damaged any electronic component...

[Antti]

Re: Ferm One electric screwdriver has no power

oh, well the admin can change this for the right place

I dont know how to test the power switch with a multimeter......

If you can see, the C3 component, is it a smf fuse? if the water did blow up only fuses..

[fzabkar]

Re: Ferm One electric screwdriver has no power

Can you tell us the markings on M1, M2, U2, U1, D1, D2?

[stj]

Re: Ferm One electric screwdriver has no power

there are solder balls and splashes on it,
it needs to be attacked with a stuff brush & some IPA

[budm]

Re: Ferm One electric screwdriver has no power

The slide switch is for Forward-Reverse function, and the micro switch is for the Trigger ON/OFF right?

[kc8adu]

Re: Ferm One electric screwdriver has no power

u1 and the 2 mosfets is undervoltage protection.if battery low that shuts off unit.
u2 is the charger.
probably a tp4056.
whats the battery voltage?

[fzabkar]

Re: Ferm One electric screwdriver has no power

C3 is a capacitor.

Not sure if the battery question related to the battery's actual voltage or its spec, but it is a 3.7V 1300mAh Li-Ion type.

[stj]

Re: Ferm One electric screwdriver has no power

crappy spec, you can get those cells upto atleast 2700ma
makes me wonder what's in my one.

[kc8adu]

Re: Ferm One electric screwdriver has no power

its current voltage.if too low low voltage cutoff occurs.

C3 is a capacitor.

Not sure if the battery question related to the battery's actual voltage or its spec, but it is a 3.7V 1300mAh Li-Ion type.

[kc8adu]

Re: Ferm One electric screwdriver has no power

thats a high rate cell.it can probably take 30a continuous and 100a pulse discharge.i have 3500 mah 18650's here but they have ptc protection.
i bet a tesla cell would do ok.
i put 10 of them in a milwaukee pack 5s2p.
they do fine.
but that grade of cell is way out of budget for that screwdriver.

crappy spec, you can get those cells upto atleast 2700ma
makes me wonder what's in my one.

[budm]

Re: Ferm One electric screwdriver has no power

I would hope that the OP has already tested the Voltage of the battery already before asking for help.

[megaraider]

Re: Ferm One electric screwdriver has no power

laughing to myself...
scrolled down and no one is helping the guy!
btw,
gave up using bat on screwdrivers a long time ago:
if i 'forgot' to use it... when picked it up » no bat left » do it by hand
if i used it for some extensive or long period job » bat died » do it by hand
thus,
using them with an extensible long power cord connect power source

[budm]

Re: Ferm One electric screwdriver has no power

"scrolled down and no one is helping the guy! " The OP never comes back and tell us of what he had tested and test result, hard to help some one when there is no feedback. May be you have crystal ball to know what OP have done so far?
OP said he know how to use the meter but does not have enough experience to know if C? is capacitor or fuse.
You can help by telling us which component/s on the board are/is bad.

[rhomanski]

Re: Ferm One electric screwdriver has no power

Sim, sim, salabim, C15 is toasty.

[Antti]

Re: Ferm One electric screwdriver has no power

I asked the question 2 days ago, gotta go to work. This is only a hobby to me.

The slide switch is for Forward-Reverse function, and the micro switch is for the Trigger ON/OFF right? ---- Yes


I would hope that the OP has already tested the Voltage of the battery already before asking for help. ---- battery is fine


I dont have the time to measure components now, but i do it today..... or tomorrow...

[megaraider]

Re: Ferm One electric screwdriver has no power

hard to help some one when there is no feedback

That's a custom problem, i agree with you @budm!
Most junior, not only but mainly, start a thread and forget to give feedback:
either because they lost interest along the way or because they solved the problem.
Seen a lot threads where the last one happened and they failed to leave feedback,
even when prompted by participating (senior or not) members.
Since we are all learning with both our experiences and others this is frustrating imo

Nevertheless @Antti just posted explaining himself and leaving some feedback.

[kc8adu]

Re: Ferm One electric screwdriver has no power

still no voltage reading.define "fine"

[stj]

Re: Ferm One electric screwdriver has no power

put a meter across the battery and tell us the voltage both normally and when the charger is plugged in.

btw, does the motor run if you connect it to something else?