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      Webinar Recordings Index Page   11/07/2017

      On-demand appliance repair training videos for Professional Appliantologist members Over 30 hours (and growing!) of original, high quality appliance training webinars developed and given by yours truly are at your fingertips, on topics you won't find anywhere else. Fill in those knowledge gaps, strengthen those areas of uncertainty, and boost your skills. Watch on mobile or desktop at your convenience whenever, wherever.  Ultra Short Primer on Basic Electricity, Circuits, Ohm's Law, and Schematic Reading (Length: 1:04:48) Basic Refrigerator Troubleshooting (Length: 1:10:45) Schematic Reading Workshop, 10/2015 (Length 1:19:08) Troubleshooting Strategies for Computer-Controlled Appliances (Length: 48:34) Semiconductors and PN Junctions (Length: 1:04:37) Appliance Temperature Sensing Devices & Technology (Length: 1:27:33) Voltage Measurements, Meters, Ghost Voltages, and Triac-controlled Neutrals (Length: 1:29:32) Troubleshooting with Tech Sheets, Part 1, 4/2016 (Length: 1:09:26) Troubleshooting with Tech Sheets, Part 2, 4/2016 (Length: 1:21:11) Tech Sheet Review, 4/9/2016: Bosch Speed Cooker, Amana Refrigerator, GE Glass Cooktop Range (Length: 1:22:58) Pulse Width Modulated (PWM) Switches used in Samsung Switched Mode Power Supplies (SMPS) (Length: 27:07) PWM Computer Cooling Fan in a Whirlpool Refrigerator (Length: 14:53) Understanding AC Split-phase Household Power Supplies (Length: 52:41) Troubleshooting a Samsung Electric Dryer without Disassembly using Live Tests and the Schematic (Length: 22:47) Troubleshooting a Bosch Dishwasher No-Heat Problem using the Schematic and Live Tests (Length: 15:38) Linear Motors and Linear Compressors (Length: 55:54) Bi-directional PSC Drive Motor Systems in Whirlpool VM Washers (Length: 56:52) Appliance Service Call Structure and Troubleshooting Strategies (Length: 1:00:16) The Ten Step Troubleshooting Tango and Workshop Exercises (Length: 1:35:39) Troubleshooting Ten-Step Tango Advanced Workshop (Length: 1:32:06) Ten-Step Tango Troubleshooting Workshop: Refrigerators (Length: 1:35:57) Whirlpool Duet Washer Schematic Analysis & Whirlpool Dryer Moisture Sensor System (Length: 1:03:04) Neutral Vs. Ground, Inverter Microwave, Digital Communications, Loading Down in DC loads, and more! (Length: 1:14:45) Gas Oven Service Call After a Parts Changing Monkey (Length: 36:04) AFCI and GFCI Circuit Protection Technology (Length: 41:26) Troubleshooting Samsung Refrigerators and more (Length: 1:29:58) 3-way Valves and Dual Evaporator Refrigerators (Length: 1:15:45) Split-Phase Compressors and PTC Start Devices (Length: 1:11:57) Gas Dryer Ignition Systems (Length: 53:50) Refrigerator Sealed System Thermodynamics, Part 1 (Length: 43:07) Refrigerator Sealed System Thermodynamics, Part 2 (Length: 1:09:09) Refrigerator Sealed System Thermodynamics, Part 3 (Length: 1:11:56) Refrigerator Sealed System Thermodynamics, Part 4 (Length: 37:45) Refrigerator Sealed System Thermodynamics, Part 5 (Length: 16:35) To access these webinars and all the other info-goodies here at Appliantology, become a Professional Appliantologist today. If you need cost-effective, time-flexible, state-of-the-art appliance technical training, check out the Master Samurai Tech Academy.
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      [Webinar] Appliantology Workshop   11/09/2017

      Information is the name of the game in the appliance repair trade today. Appliantology is a powerful information tool for the professional appliance repair technician. But just like with any of the more capable tools in your tool bag, many of the more powerful features are hidden from you unless you "read the manual." Ugh! Who wants to do that? Well, this is one time when you don't have to! In this webinar, Team Samurai will personally walk you through the site and show you many of the useful and powerful features that even long-time users probably never knew existed.   

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How to Fix All Serial Communications Error Codes in Whirlpool-built Front-load Washers

Samurai Appliance Repair Man

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The dreaded “serial communications error” in Whirlpool-built front-load washers appears as various codes, depending on the particular model. On the Old-Skool Duet washers, the most common communications error code was F-11: communications error between the Central Control Unit (CCU) and Motor Control Unit (MCU). On the new model Duet washers, this same error has been re-labelled as F-28. On some Maytag front loaders (all built by Whirlpool, in case you didn’t already know that), you may see an F6E2 fault code, which is a communications error between the CCU and the User Interface (UI) boards.

Many a fine battle-hardened appliance warrior has been befuddled by these error codes and have needlessly soiled their undergarments throwing every control board in the box at it.

But these serial communications error codes all have one big thing in common:

They are almost NEVER caused by a bad circuit board! Instead, they are exactly as the error code description says: a COMMUNICATIONS error between two boards. In other words, a bad connection.

Oh, I know— you’ll hear some guys swear it was a bad board because they replaced the such-and-such board and it fixed the problem, so it had to be a bad board. But I’m here to show you that in 99.9999% of these cases, the board itself is perfectly functional but the real problem is the CONNECTIONS to the board.

“Uhh, howzzat, Samurai Smart-ass Guy?”

Ahh, Grasshoppah, make still your mind and the Samurai shall reveal the truth unto thee. And the truth shall make you free. Come with me now on a journey of Total Appliance Enlightenment™…

Let's think about the modern front loading washer and the average laundry room for a minute. In these front loaders, you have at least two (CCU and MCU) sometimes four (CCU, MCU, UI, and Steam Board) different boards that all need to talk to each other and pass data back and forth: digital data, voltages. How do they do this?

Since they haven’t incorporated internal Wi-Fi into appliances yet, all these boards are connected to each other by special wire harnesses called serial communications cables. All this data exchange is fact-checked and verified by a process called “handshaking” (yes, that’s what it’s really called). If, at any time during this continuous process of passing data back and forth an error is discovered during the handshaking, the CCU throws a serial communications error. The closest it can get in the error code is by telling you which two boards had trouble talking. But that’s close enough!

So what causes these handshaking errors? Lots of things! In fact, given the conditions that these washing machines have to work in— lots of vibration, moisture, humidity, heat, etc.— it’s amazing they work as well as they do. But all it takes is a loose connection at a molex connector on a wire harness or an oxidized pad on the control board to disrupt that handshaking. It doesn’t even need to be a totally broken connection, just one with low enough signal-to-noise ratio that the CCU can’t tell which is signal and which is noise.

Okay, here’s the part you’ve been waiting for: the Silver Bullet Fix for these elusive and mysterious serial communications errors in Whirlpool-built front-load washers.

The harness itself can (and usually does) check good. That's not usually the problem. The problem is at the harness connection points where the molex connector on the harness connects to the boards at either end. The tines can become loose or the pads on the board may become oxidized. Here's a technique that I've used with great success in these types of problems. BTW, all modern front loaders work the same way and use pretty much the same basic technology so this solution concept for serial communications errors applies to all brands of front load washers, not just Whirlpool:

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Excellent video Samurai.  Have used the solder build-up many times.  Works great.

 

Do you recall this trade trick from "B-doubleE" school in the Navy:

Use a standard pencil eraser to clean the contacts on circuit boards.  It gets the copper looking like brand new.

 

Happy Thanksgiving and thank you for this awesome website !

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Samurai Appliance Repair Man

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Do you recall this trade trick from "B-doubleE" school in the Navy:

Use a standard pencil eraser to clean the contacts on circuit boards.  It gets the copper looking like brand new.

 

 

I remember it like it was yesterday... even though it was over 30 years ago.  I still use that trick and often tell Grasshoppers about it here at Appliantology

 

Happy Thanksgiving and thank you for this awesome website !

 

 

Happy thanksgiving back atcha, mah bruvah!  And thanks for being part this site!  

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Samurai Appliance Repair Man

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Domo, TAS!  Give it a shot next time you run into one of these and let me know how you make out.  

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