FIXED Whirlpool WFC7500VW2 No display, No power No start up

springwood

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Model Number
WFC7500VW2
Brand
Whirlpool
Age
1-5 years
2015 Whirlpool WFC7500VW2 no display, no start up, no power

Many thanks for the volumes of information here. I've searched the threads but want to be sure of a couple things before ordering parts. The WFC7500VW0 service manual has been downloaded, an extra special thanks to a Mr.Jake..

I have some limited knowledge of the workings of multi-meter so before checking every component I thought, for better or worse, I'd mention that I've traced power from the wall outlet (120) to the CCU using an AC sensor pen which measures 50-1000 volts (Ultimate Sensor AC3000). Power has been found all the way down to the motor control unit.

With all this power going around I'm still not getting any displays, lights, bells or whistles. The washer acts dead as a doornail.

The CCU Cycle Select Dial is sending power all over the place when it's turned to any setting. When off, the power stays at the dial connection.

The manual details all of the checks regarding the CCU and component readings but no mention of testing regarding the MCU ??

thanks for any info
 

rickgburton

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Those AC pens don't work very well for appliance repair. Most major components are operated by breaking the neutral side. There's no way of getting an accurate measurement. If the outlet was bad and only supplying 75V - 80V, you wouldn't be able to tell. Check for 120 VAC across P13-1 and P13-3 on the motor control.
 

springwood

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thanks rick

Would those be on the wiring diagram? I'm looking at the diagram from that L-83 2008 service manual of wcf7500vwo, the closest thing found relating to my model, and I'm not seeing either of those. I'll check the real thing later tomorrow..

Re: this sensor pen....I just use it for basic stuff so I don't die but usually I need to actually touch a wire's plastic housing for it to light up. When using it with this washer it can literally hover over a wire or component and light up which I thought was strange. I've even reinstalled the CCU face panel put the washer top back on, plug the machine in and I can get the pen to light up from the outside face of the touch pads and cycle select dial ...which again I thought was strange.

I've noticed when the wires are bundled and there's one wire in the bundle that's been disconnected, like say the wire the feeds the options touch pad circuitry and display, the pen was still lighting up at the connected end of that wire. The wire had to be moved far away from the bundle to prove to myself it really didn't have power, which obviously it couldn't have...

I'm wandering here and want to get back to the issue at hand (like where I'm going to find those contact points rick mentioned) but does anyone else think it's strange that the pen lights up when just getting close but not touching these little wires??

See the pics....that pen isn't even close to touching a wire...I realize the pen is worth little in appliance world but am I wrong to be concerned that I'm getting such strong vibes from that thing??

electricity is not my thing
 

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rickgburton

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Your pen works by detecting the magnetic field produced by AC voltage using capacitive coupling. A capacitor has two conductors or plates one positive and one negative. separated by a non-conductor. If an AC voltage is connected to the the two conductors an AC current will flow across the non-conductor as the electrons are being attracted or repelled by the voltage on the opposite plate. When you connect two capacitors in series you get a larger voltage across the smaller capacitor conductors so the live wire is the first plate in the smaller capacitor and the tip of the pen is the second plate. The air between them is the non-conductor. The person holding the pen is the first plate of the larger capacitor and the ground is the second plate with your shoes being the non-conductor between them. That makes your light turn on in the pen.

Since you're not getting anything to turn on, start by checking the outlet first. If you have 120 VAC at the outlet everything else can be checked without having the machine plugged in. The power cord is connected to the line filter so if each wire in the power cord has continuity to the line filter check the line filter by disconnecting the wires and checking for continuity across terminals A-B and C-D:
43895

Reconnect the wires and remove the IF2 connector from the CCU and measure the resistance between Pins 1 & 2. Your meter should indicate 0Ω
 

springwood

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VT
huge thanks.. FASCINATING stuff re the workings of the sensor pen...which I never thought about in that way...nor in any way, now it's going to be like an earworm thing until it gets processed..
I'll be back
 

springwood

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Word from the top says that there's a need to fix this thing sooner than later....I dunno why... we got a stream out back and some rocks

RICK!!!.....I hope you're still around

"Reconnect the wires and remove the IF2 connector from the CCU and measure the resistance between Pins 1 & 2. Your meter should indicate 0Ω" ( I failed at the quote function)

^^^^ this is where I am and sure enough (the wall outlet, cord and filter checked out at 120volts) I am NOT getting 0 ohms....I'm getting infinite.
The door switch was then checked as the manual stated on 5-5 and that seems fine...

So am I ordering a new CCU???? or is further testing required??
 

springwood

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actually, I meant was the filter checked out at 0 ohms...
also, I don't know if this means anything but while I'm getting infinite at the IF2 pins 1 and 2 (which is bad right?), when I turn the Cycle Select Dial clockwise to the next setting there's a reading of 315 ohms at the 2000K scale on my meter. Any lower meter setting shows infinite when turning the dial. When the Cycle Select dial is off the reading is always infinite regardless of being at 2000k. (which is also bad right?)
Something tells me I'm going to be the one at the stream with the rocks so any info much appreciated..
 

rickgburton

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springwood

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It arrived today so I checked it with the multi-meter and I was worried. I got infinite between pins 1 and 2 but this was right out of the box so I figured I needed to install it, connect all the wires and then check it with IF2 line filter connector disconnected as well as power to the machine. Again I got infinite at pins 1 and 2 so I was twice worried. The good news is that with this ccu unit installed the machine is back to normal, everything working as it should. Is there something wrong with how I read the meter???? I began to think that disconnecting every wire and reconnecting has made the difference but that doesn't explain getting infinite at pins 1 and 2 on both units unless I was doing the test wrong. Either way I'm ecstatic as is my better half that this thing is working!!!
 

rickgburton

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Check if you're meter is on the correct ohms setting (lowest). Glad to hear it's working. Good job!
 
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