Siemens waching machine Siwamat plus 7421 repair-need schematics

[dorke]

Washing machine is not working at all only line lamp is on.
before it was tripping the current fuse (not residual!) after a few seconds with a loud boom coming out of it .
Now that I opened it not tripping anymore just doesn't work at all.
Any ideas?

Anyone has service manual or schematics?
The control board is :
AKO BSHG 306 0157 AC2

thanks

 

[Martaine2005]

Hi dorke,
I can't find a schematic for it.
When you say the line lamp is on, is that connected directly to mains in (neon) or through a switch on the machine?

Some items to check.
Filter capacitor, normally located on the bottom somewhere.
Motor.
Pump.
Wires for short circuit.
Heating element. (if it has one)
Thermal fuse.
They are usually self explanatory except the main control board.

If line lamp is on, trace the line through.
A loud boom could be a lot of things.
Motor seized in operation, belt broke and hit casing etc.

Can you take it apart? top off, sides and back? and post some pictures.

Martin

 

[Minder]

If it is fitted with one of the new outrunner 3ph motors it is direct drive and has no belts or gearbox, if so it could be the 3ph electronic drive unit.
M.

 

[dorke]

I opened the machine side,the model is a top loader .
photos are a bit of a problem for me now.

I disconnected and removed the control board (4 connectors) .
There is no visual damage in the machine:belt is fine.
Looks like the mains lamp is neon.
it lights up without the control board in the machine, when the thermostat dial is moved from 0 to I and beyond.
What would the the mains wires inputs to the control board be? the largest diameter maybe?any specific color for the Siemens machines?

I will try to trace the mains line in the machine


photos are a bit of a problem for me now.
Here are photos from the web of the control board and the panel.

 

[Martaine2005]

I am not sure for different countries.
But UK would be BROWN = Live, BLUE = Neutral and green/yellow = Earth.
But the 'loud boom' has to show some kind of failure somewhere.!!
Does the motor spin by hand? Pull the belt to rotate it.
Turn the drum and try and see if something has seized.
If you feel a churning on the motor, the bearings have probably 'gone' and caused an over current situation, causing the breaker to blow.

Martin

EDIT: flex size would be 2.5 three core.
EDIT: 2, My electrical wholesaler has 1.5 3 core listed for 16 amps and white appliances.
I only use 1.5 for lighting.

 

[dorke]

Problem fixed-machine is now working.

The fault was the door-interlock(door switch).
It is a 4 contact one (YMOS part):
pins 1-2(PTC) get the 220volts and close the connections 4-5(switching the Neutral line).
Since I couldn't get the schematics of the machine ,I had to trace the connections(look at the drawing I made).



The PTC was totally blown(infinity resistance),when I took the device out it was "rattling" when shaken.
The interlock was the one making the loud "boom" sound but looks perfectly good from the outside.
The cause of the fault was a leaking boiler above the washing machine.

Since I have no door -interlock to replace the faulty one with ,
I fixed the machine by connecting the wires from pins 4-5 with a crimp-terminal "piggy back" male to override the switch.
I left the door interlock, so the door would lock in place.
When I can get a replacement I would put it in.

This practice is not recommended but since the machine is a top loader there is no water spill danger,
only the safety issue of opening the door while the drum is still spinning .

 

[Martaine2005]

Ha! glad you sorted it and found the problem.
So, maybe, you was exagerating with the loud boom!

You must have known the boiler was leaking before it 'broke' the washing machine!!!
Good on ya for sorting it.

Martin