110.47081600 Kenmore Washer HE5t - F28 error

[rover_nut]

Model Number

110.47081600

Brand

Sears Kenmore

Age

More than 10 years

Unplugging and waiting 10-15 minutes doesn't reset it.
I replaced the MCU about 11 years ago. - https://www.applianceblog.com/mainforums/threads/fixed-he5t-just-beeping.23867/#post-119786 which fixed a different issue.
My understanding is that F28 is the CCU, MCU or wiring between the two.
I've done a continuity test of the wiring between the CCU connector and MCU connector and the resistance looks pretty much spot on.

Is there a way to test the CCU and MCU to determine which is bad? Based on my previous issue with this washer I'm guessing the answer is no, but want to confirm before ordering either.
Is there something I can disconnect from either unit to increase the odds of determining which is bad?
If not I guess it's a crapshoot which is bad so unless otherwise recommended I'll replace the CCU, since I replaced the MCU last time and it's not as old. But maybe the MCU is more prone to failure?

BTW, after reconnecting the serial com, put it on express wash.
It clicked like it was starting, ran water for about 15 seconds and stopped. clicked a few more times then went silent and started counting down.
No idea if that points to anything specific.

Regards,
Tom

 

[jeff1]

Hi,

I will let someone else see about your other questions. I found this, a copy...

F28

Communication error between the main electronic control board and the motor control board

Unplug the washer and check the wire harness connections between the main electronic control board and the motor control board. Check the wire harness connections between the motor control board and the drive motor. Reconnect any loose wires or replace any wire harness that you find damaged. If those wire connections are okay, check the wire connections between the door lock/switch assembly and the main electronic control board. Reconnect any loose wires or replace the wire harness if damaged. A bad door lock/switch also prevents the motor control board from getting power, resulting in the F28 code. Replace the door lock/switch assembly if damaged. Replace the motor control board if the wire connections and door lock/switch assembly are both okay

Motor control board, door lock/switch assembly, wire harness

jeff sr.

 

[rover_nut]

The door lock causing F28 is news to me, but the lock is working normally so I'm going to assume that's not the problem..

 

[rover_nut]

So I replaced the CCU and that didn't fix it.
Additional symptom info is that when I press start, the door locks, water runs through the soap dispenser, the door unlocks, water stops, door locks and then nothing else happens. Timer starts counting down and after a while the F28 code is thrown, so maybe it is a faulty door lock.

 

[Jake]

Make sure you have the front access panel back in place so the grounding switch is made.

Look here:

FIXED - WFW8410SW00 Whirlpool duet sport error code F28

You guys are amazing! I repaired my fridge in a couple hours for free because of you're info on this site, the appliance repair guy wanted to replace parts that I didn't need to. THANK YOU! Now, I hope I can find help on my Whirlpool Washer Model WFW8410SW00. The f28 serial communication error...

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I fixed it. Now I feel like an idiot.
After spending lots of time trying to figure it all out, and looking for loose connections I realized there was a grounding switch on the front bottom corner.
I had the front panel off to clean out the drain. I was having a hard time getting the screws back in and I left them off. I asked my husband to put them back on (2 weeks ago) so the panel kept falling off each time it got bumped. I of coarse thought I had loosened something, cleaning it out and never noticed the stupid switch! I only had the error message some of the time (probably when the panel was on the ground) and never put 2 and 2 together.
Thanks for your help.

 

[rover_nut]

Make sure you have the front access panel back in place so the grounding switch is made.

Interesting. I have to admit the cover has been off for 11 years and the washer has been working fine.
Maybe the switch has been stuck closed and popped open. I'll check.

 

[rover_nut]

Well, I put the lower front panel back on so at least now I can get the door to unlock. But still having same symptoms.
The door locks, water runs through the soap dispenser, the door unlocks, water stops, door locks and then nothing else happens
I'll test the door switch next.

 

[rover_nut]

I'm looking in the manual to test the door lock, but the illustration of the CCU bears little resemblance to mine, so have no idea which component connection to test.

 

[Jake]

Read what Rick said here to test it:

FIXED - 110.49962603 F28 error code

washer is right at 2 years old and was running great. nothing to indicate an issue was about to happen. i researched the f 28 code and understand what it means. i found a checklist online of a list of things to check and everything checks out. getting power to the door locks and the mcu. i...

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