Need help troubleshooting a Whirpool control board (it's not the caps!)

[UL161]

I have a Whirlpool Side-by-side refrigerator that is only a few years old and I am now experience a problem where the cooling coil valve that enters the refrigerator side is not opening consistently. (the freezer is perfect ice cold). I have found out the problem can be overcome by simply pulling the power for a few minutes. Upon restart it works for some period then randomly stops. In speaking with a tech they claim this issue is likely due to an issue on the main control board. So I decided to pull it and I thought one cap looked bad so I replaced all 4... I thought I had solved it but ~24 hours later, it exhibited the same intermittent symptoms. Anyone have a clue what other part on this board might be the issue???

[stj]

maybe the valve is sticking - connect a meter or lamp to it

[UL161]

Definitely not a valve issue.. it is electronic

[stj]

well it could be a relay issue - and c58 doesnt look great - top should be flat
i dont think c58 is the issue - just something unrelated.

[UL161]

actually agree with you. I replaced c58 + the other 3 caps... (picture is before my repair).... still having the issue..... If it were a relay... I would assume that would just be dead and unrecoverable with my power off power on trick... what do you think... I am certainly not an expert however so not positive about my statement on that point, just my understanding how the part works.

[stj]

no, what useually fails is the switching contacts get pitted from arcing and then they get unreliable.
maybe you can switch them with a battery and then meter the contact resistance but thats not reliable without a load.

[sam_sam_sam]

Definitely not a valve issue.. it is electronic

Where is the power supply board located at because I do not see a switching power supply transformer or the switching power supply regulator on this board because you might not be getting any power to supply power to this board

I have worked on this type of board before on another refrigerator and it was a power supply problem so I would look for the power supply board and see if it powering ON or not

[UL161]

sam_sam_sam.... Thanks for this suggestion.. I am actually thinking that the power supply board might be causing the issue to some extend too. It is actually on a separate board next to this one... (see this link on ebay... Board is basically this model. ) I think one 10uF Cap on this board looks a bit suspect... Maybe I should just try to reCAP the power supply board too. What do you think??

[stj]

OMFG!
get that board out and inspect it,
the one on the ebay link had so many cracked solder joints it was hard to believe!

[sam_sam_sam]

OMFG!
get that board out and inspect it,
the one on the ebay link had so many cracked solder joints it was hard to believe!

That is not unusual for Whirlpool controllers board to be like that sometimes after a few years in service poor quality control on the part of manufacturers of these boards really sad that they do not have better quality controls in place but it not just Whirlpool that has this there are a lot manufacturers that seem to have this problem as well

[UL161]

Here are a few picture of my power control board.. I don't think it looks in as bad shape as that one on ebay... That said, I think it is probably worthwhile to just replace the 7 caps on the board. Would you agree?

[sam_sam_sam]

sam_sam_sam.... Thanks for this suggestion.. I am actually thinking that the power supply board might be causing the issue to some extend too. It is actually on a separate board next to this one... (see this link on ebay... Board is basically this model. ) I think one 10uF Cap on this board looks a bit suspect... Maybe I should just try to reCAP the power supply board too. What do you think??

I highly recommend that you use a magnifying glass to see the fine cracks around the pin soldering joints to the board or if see flux around the pins or around the pin holes to solder traces if you see either one remove the solder and redo them

You need to look at pin connectors on this board for bad-rings around that look like the solder separation from the pins to board because or gaps between the pins and solder joints to the board Whirlpool has had some very serious issues with this in the past I have repaired a few there board in the past

[sam_sam_sam]

Here are a few picture of my power control board.. I don't think it looks in as bad shape as that one on ebay... That said, I think it is probably worthwhile to just replace the 7 caps on the board. Would you agree?

Take a picture of the bottom of the board so I can see the soldering joints and the traces

What is the part number of the device that is mounted on the heat sink

Because iI think I see the switching power supply regulator because if I see it right it has 5 or 6 pins

By the way the capacitors that KZE or KY are a very good series in caps I would not necessarily replace them at this point but if there is a capacitor near the switching power supply regulator I would definitely recommend changing it especially if the UF value is less than 100uf it might be 10uf, 22uf, 33uf, 47uf