Bosch SGS6612GB/12 main circulation pump not running

[paltibine]

The white wire attached to the terminal on that black relay seems permanently connected to terminals 2 & 3 on the motor. These are the 2 terminals that are connected together at the motor.
If I measure resistance between the terminal on the black relay and terminal 4 it measures open circuit but if I use the buzzer on the meter it buzzes out as short. Not sure what that means?
The black box gets warm when the machine is running even though the motor itself isn’t running.

[paltibine]

The terminal on the black relay that connects to the white wire seems permanently connected to terminals 2 & 3 (these are the ones connected together on the motor). If I measure resistance from the black relay terminal to terminal 4 on the motor it reads open circuit but if I use the buzzer on the meter it buzzes as a connection. Not sure what that means?
The black relay gets warm when the machine is running even now when the motor isn’t working.

[electrofix]

cant find a diagram for your model
closest i can get here is one with 3 terminals

the fact the black relay is getting worm sounds like there is power to the motor
its a toss up now between motor or relay fault

would need to see some pics of how its all connected to be able to make any kind of judgement

Dave

found a pic

but no wiring info

remove all wires and the relay and measure beween each terminal in turn and see what readings you get. dont use the buzzer use an ohms scale

[paltibine]

I have to confess I’m struggling to remove the relay. I think it’s just the clips on the terminals and I found those difficult enough when I could see them. This is behind the relay and I’m working blind. Not enough space to get a long nose pliers in there and my fingers are a bit too long to get into the right position. I could just force it but would risk breaking the motor terminal or the relay.

[electrofix]

ok give me some reading without removing relay but also incude readings through the relay
let see if it tells me anything

Dave

[paltibine]

I have a couple of readings from the motor with the relay still on.
1 – 4 (the 2 right hand terminals) 11.7 ohms
1 – 2/3 open circuit
Relay terminal – 4 open circuit
Relay terminal – 2/3 open circuit
Relay terminal – 1 open circuit
Does that tell you anything?
I’m going to be away for a few days now so won’t be able to do anything else till the weekend.

[electrofix]

well we have at least one winding between 1 and 4

when you measure across the relay terminal what ohm scale were you using ?

there is a chance that the relay is faulty causing this. i cant be certain at all and it may boil down to whether you want to take a chance to see if it works

Dave

[paltibine]

OK – I’m back on the case!
You made me think about the ohm scales and I tried again using the 200 ohm scale and now I also get:
1 – 2/3 is 34 ohms
Relay terminal – 1 34 ohms
Relay terminal – 4 22 ohms
Relay terminal – 2/3 0.2 ohms

Does that look right for the motor?

[electrofix]

paltibine wrote:OK – I’m back on the case!
You made me think about the ohm scales and I tried again using the 200 ohm scale and now I also get:
1 – 2/3 is 34 ohms
Relay terminal – 1 34 ohms
Relay terminal – 4 22 ohms
Relay terminal – 2/3 0.2 ohms

Does that look right for the motor?

well am confused with some of the readings

first one is that term 1 to either 2 or 3 is 34 ohms
second relay term 1 34 ohms to where ? and which relay terms are connected to where ?

did you remove the wires are you can get feedback resistances through the harness ?

etc

Dave

[paltibine]

Sorry! I’ll try and clarify.
I havent been able to get the relay off the motor and when I say Relay terminal – 1 I mean resistance between the relay terminal that connects to the white wire to motor terminal 1. So all the numbers are the motor terminal numbers and Relay terminal refers to the relay terminal that isn’t connected to the motor.
All the wires are disconnected.
Does that help?

[electrofix]

any chance of a pic as to where the wires go to try to get my head round it

found a pic of the relay motor online for an american machine but they will be similar

if am right relay connects to 4 and 1 on motor

if thats the case the motor is powered up when you get live and neutral across the relay third terminal ( no connected to motor and 3/2 on the motor that are connected together

Dave

[paltibine]

The relay is connected to 4 and 2/3.
I’ll get a picture tomorrow.

[electrofix]

oh yes see that now i look closer

so power should be between relay wire and 1 am hoping

Dave

[paltibine]

The relay terminal seems to be permanently live with a wire from the main switch. Putting mains on the relay terminal puts mains onto 2/3 (either through the relay or through the motor). Pin 1 never seems to have any volts on it.

[electrofix]

am interested in the grey wire which i i read it correctly is on terminal 1

remove grey wire and measure resistance from terminal 1 on the motor to the rest of them

am looking to see if i get a coil or is it open circuit

Dave

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