BOSCH Slimline Dishwasher (SD13G1B) control module

[Phil Grant]

Hi,
My Dishwasher packed up yesterday and there appears to be no power, the display doesn't power up etc.

I've stripped the front of and checked that the mains is getting to the control module, and it was, so I removed the control module and opened it up to have a look.

I found the Power controller IC had let then smoke out and, what I think is a 2W resistor, has gone open circuit due to overheating.

2020-01-14 18.56.44

• Phil Grant
• 14 Jan 2020

Open circuit resistor.
Guess the value!

2020-01-14 18.56.18

• Phil Grant
• 14 Jan 2020

Power IC with crack

because of the overheating I'm not sure what the value of the resistor is, the datasheet for the LNK304GN shows an 8.2 ohm resistor in the application circuit but the band colours don't match that.

I can get a new IC from RS but does anyone have a clue what the value of the resistor is?

Thanks.

 

[Phil Grant]

Update
I removed the resistor and the colours were less damaged underneath and I think it's a 10 Ohm resistor, the datasheet states a fusible resistor should be used but I don't think the one I've removed is fusible.

 

[Phil Grant]

Just in case anyone has the same issue, I replaced the resistor with a 3W 10 Ohm one and replaced the LNK304GN and everything has powered up OK and it's working fine, now to see how long it will last!

It cost me just under a fiver for the parts (had to buy 5 of the ICs) instead of around £100 for a new controller.

 

[Phil Grant]

Another update, it stopped working again ......... resistor went open circuit so I suspect that it wasn't 10 Ohms so I got the old resistor and broke it in half and as it was wire wound I could measure some sections of the wire coil with a meter.

The bits I could measure added up to 30 'ish Ohms so I think it could have been 100 Ohms, time to try a 100 Ohms resistor instead.

 

[Phil Grant]

Last update ....Two weeks and all is well. the 100 Ohm resistor seems to have done the trick.

 

[Licklieder]

Hi Phil,

My slimline dishwasher has just failed seemingly with the same fault - the resistor has gone open circuit and it looks like the power IC has small hole in it, though a slightly different place to where yours failed.

Is your fix still holding? like you i can't quite make out the resistor colours - could be brown - silver - red (looks more pink) - gold; brown - blue - red - gold. other than the brown and gold, the other two could be anything. I'm curious to know if your 100 Ohm resistor is still working.

I assume from your description of having to buy 5 IC's from RS it was this one https://uk.rs-online.com/web/p/buck-converters/5254167/ (PDIP SMD package) you purchased - the other package (SMDB) being available in minimum lots of 50.

Matt

 

[Phil Grant]

Matt,
Yes mine is still working with the 100 ohm resistor, those ics look the right ones, I can check the exact order later if you like.

Cheers,
Phil

 

[Diver Fred]

Had the same problem a couple of years ago (with the same type of DW). Mate who is an electronics engineer into servicing electronics in domestic, industrial and entertainment kit looked at it and did the work. Chip replaced. Resistor replaced - 100 ohm wirewound, Mate used a 5 watt resistor to replace the damaged one.

 

[Licklieder]

Thanks both. I'll order my bits and when they arrive give it a go. I'll be back with an update once its done - which may take some time given the current state of affairs

 

[Chris Giles]

My dishwasher died 2 days ago and is now working again - thanks to your post and RS!
Chris

 

[Licklieder]

Just got my parts delivered thanks to RS. waiting now for the soldering iron & bits to arrive. looking forward to not washing the dishes tonight...

 

[Licklieder]

An update on what happened with repairing my controller -

Got all the parts and was ready to go. 1st cheap (Chinese) soldering iron failed to work so back it went and off to TLC i went to get a better one. Found even with that one that i struggled to unsolder the components from the board, and it wasnt' long before the solder stopped melting on the iron tip. After a bit of head scratching I realised that the solder I had purchased was lead free (99.3% Sn/ 0.7% Cu) had rapidly corroded the soldering iron tip and was preventing it from being wetted. Seems this can be a common occurrence with some tips / lead free solder combinations.

So, had to order some spare tips, get some lead solder - not as easy as it appears but a popular online auction house came through - and a few (covid delayed) weeks later i'm ready to have another go. Only now I find that my previous attempts had damaged the board & destroyed two of the surface mount pads. Grrrr.

Long story short, I have had to purchase a replacement controller.

Frustrating as i was looking forward to this being a simple, cheap electronic fix. Though i do now have all the bits i need to fix the next one when it fails....

 

[deridere]

An update on what happened with repairing my controller -

Got all the parts and was ready to go. 1st cheap (Chinese) soldering iron failed to work so back it went and off to TLC i went to get a better one. Found even with that one that i struggled to unsolder the components from the board, and it wasnt' long before the solder stopped melting on the iron tip. After a bit of head scratching I realised that the solder I had purchased was lead free (99.3% Sn/ 0.7% Cu) had rapidly corroded the soldering iron tip and was preventing it from being wetted. Seems this can be a common occurrence with some tips / lead free solder combinations.

So, had to order some spare tips, get some lead solder - not as easy as it appears but a popular online auction house came through - and a few (covid delayed) weeks later i'm ready to have another go. Only now I find that my previous attempts had damaged the board & destroyed two of the surface mount pads. Grrrr.

Long story short, I have had to purchase a replacement controller.

Frustrating as i was looking forward to this being a simple, cheap electronic fix. Though i do now have all the bits i need to fix the next one when it fails....

Hi All,

Hope your fix is still working.

I have a Bosch srs45e42gb that could have the same issue. Mine however does not have the very bad burn-marks around the resistor, but I can sense electronics burn smell around the resistor and some yellowish mark on the white relay. The resistor is currently showing an opened circuit so will start with the replacing the resistor ( and will order the IC just in case).
Is this resistor fit for the job ?
https://uk.farnell.com/multicomp/mc...und/dp/1903931?st=WIREWOUND RESISTOR, 100 OHM

I suspect the burned resistor was the symptom of another component going bad - the relay or the IC?
I would like to keep the dishwasher it as close to OEM as possible, so would appreciate you input.

 

[Phil Grant]

Hi,
That looks likke the right resistor to me, for the cost I would probably get the IC replaced as well, have you measured the resistance on the resistor to confirm it's gone faulty?

Phil

 

[Licklieder]

The resistor and chip are relatively cheap and readily available so if indeed faulty I would replace both too.

Based on my experience i would also get yourself some lead based solder to de-solder / solder with - not the lead free stuff which was a bugger to work with and resulted in my destroying the surface pad. I'm sure there are good, workable lead free solders but the stuff i got was terrible. With hindsight, I should probably have tried a hot air soldering gun to remove the surface mount chip too - but that's another thing to buy for a 'cheap repair'. Mind you, having to buy a replacement controller from Bosch is a very expensive way to fix a couple of blown components...