Hi there,

I have samsung eco bubble washing machine.

I was using multimeter probes to test voltage and the probe slipped and it seems something was shorted.

Now the machine won't power on.

PCB dc41-00189a

I'm a Newbie Please help me to troubleshoot this pcb.

 

What were you investigating to start with?
What did your probe touch?

 

What were you investigating to start with?
What did your probe touch?

What were you investigating to start with?

I was checking the voltages to see why the Drum would rotate and stop.

What did your probe touch?

My probe touched somewhere between the contacts of those large capacitors.
The board was plugged in.

Something shorted and the machine went dead.

I am getting 220vac at the main relays.

I'm guessing issue is one dc side.

 

I found this Schematic but I am not sure how to read it.

Also, there are 2 DC voltage regulators... The Supply voltage to those is off and the output is off SINCE I experienced the shorts. Their voltages were okay before.

Please see attached photos

 

Can you measure the DC from the bridge rectifier, also check the fuse ..

 

Can you measure the DC from the bridge rectifier, also check the fuse ..

The 2 fuses have continuity and are not showing any signs of being blown.

When I measure DC OUTPUT from the Bridge Rectifier I am getting about 3vac but if I put the multimeter to AC then I get 125volts on the dc + & - output.

 

The 2 fuses have continuity and are not showing any signs of being blown.

When I measure DC OUTPUT from the Bridge Rectifier I am getting about 3vac but if I put the multimeter to AC then I get 125volts on the dc + & - output.

I meant 3VDC

 

If you're getting 125V AC on the centre two pins , then you should be getting over 125V DC on the outer pins ,

Note the bridge rectifier is marked + ~~ -

 

If you're getting 125V AC on the centre two pins , then you should be getting over 125V DC on the outer pins ,

Note the bridge rectifier is marked + ~~ -

I am getting 3VDC on the outer 2 pins marked with + - ... If I measure in AC I am getting 125VAC on those 2 outer pins.

Does that mean the Bridge Rectifier is defective?

 

The outer pins are DC the centre pins are AC , so measure them correctly, put your meter on DC and the leads on the outer pins .

 

The outer pins are DC the centre pins are AC , so measure them correctly, put your meter on DC and the leads on the outer pins .

I am getting 13VDC on those 2 outer pins.

 

Ok that's definitely Wrong, what is the AC voltage on the centre pins.

 

Ok that's definitely Wrong, what is the AC voltage on the centre pins.

For the center pins AC now, if I put the BLACK multimeter probe to ground on the body of the Machine and put the RED probe on either AC pins I am getting 125VAC on each pin.

If I put the BLACK probe on one AC pin and the RED probe on the other AC pin then I AM Getting about 17VAC.

 

Should I be getting 220VAC or MORE across those 2 AC pins?

I have attached photo

 

Yes if your mains supply is 220V.

 

Yes if your mains supply is 220V.

Yes, my mains is 220vac. So where can I check for the fault since I am only getting 125vac across those 2 AC pins on the Rectifier?

I am getting 220vac from the main relays (see attached photo)

Please guide me to where to check for fault.

 

Follow the mains lead in upto the bridge rectifier and you will come to the fault.

 

Follow the mains lead in upto the bridge rectifier and you will come to the fault.

Thank you Dave.

I have followed the main leads and I have found something I think is interesting.

(I have attached photo)

I measure 225VAC between both legs of the input relay up to the 1st leg of this Diode.

Once the current passes through the Diode then the Voltage on 1 leg of the relay falls to 60VAC.... IS THIS normal?

When I measure continuity across the resistor I am getting 600ohms.

Please guide me from here.

Also let me know if I am Checking in the right direction.

 

I am also measuring 310DVC between then - DC output of Rectifier and a Diode connected to the + DC output of Rectifier.

Please see attached photo

 

Can anyone please help me?