Magic Chef MCWC44DZ E4 error

I found the connectors corroded for both fans. The lower fan connector had one pin that was completely destroyed. I hard wired the wires together as a test and the unit is working perfect. Check the fan connectors by removing the two screws that hold the shelf in place and cafefully slide out fron the cooler. You will have to disconnect several connectors hidden in the right side of the shelf before you can completely remove it. Good Luck.

I did exactly what bobml3 did. I am not an electrician but I'm willing to try things before hiring one. My upper zone was not cooling because the fan was not running. I had a E3 error. By opeing the front door, removing a screw from either side of the middle shelf and also taking off the front cover of the middle shelf, I was able to follow the wire which led to the upper fan. By checking the connectors, I found the one black one connected to the back of the shelf going to the upper fan was corroded. I cut the connector off and stripped the wires and used electrical wire to connect them. (Hard wire?). When I plugged unit back in- WaLa. Not bad for a chick!!!

Bobml3 - can you tell me more about how you were able "to disconnect several connectors hidden in the right side of the shelf before you can completely remove it?" also, do you need to remove the 4 screws that surround each fan or just the 4 screws in each corner of the large back cover? thanks!

I followed the directions provided here by bobml3, it worked perfectly. Proactively hardwired the upper fan as those connections were starting to show corrosion. Definitely needed wire strippers for 20 gauge ($9) and I also ended up using cold/thermal electric tape ($2) to protect the new connections. Fans are running again and temperature on both zones are dropping from room temp. The hardest part was disconnecting the plastic connectors on the right hand side of the shelf as they are tight and in a difficult space to work with your fingers. A great fix for a $12 investment in tools and supplies.

Where can you order new fans for the unit?

+1 on the corroded connectors. The connectors to the fans get moisture in them and corrode.

I had ordered a fan before getting into it. I could have used the existing fan because I ended up just stripping the wires and hard connecting them. Only tool needed is a phillips screwdriver. There are 3 connectors on the side to remove the control panel shelf. Its a pretty simple job.

If the fan connector(s) short out due to moisture build up it can damage the fan power supply which means if you follow the steps above and still have the E3 E4 error then most likely the fan power supply was damaged. In my case I followed the suggestions above and twisted the fan connector wires together and still had the E3 E4 errors and fans were not spinning. FIXING THE POWER SUPPLY IS AN ADVANCED STEP AND NOT FOR SOMEONE WHO IS UNFAMILIAR WITH ELECTRONICS AND WORKING AROUND 120VAC ***IF YOU WISH TO CONTINUE TO TROUBLESHOOT AND REPAIR THE FAN POWER SUPPLY THEN PROCEED AT YOUR OWN RISK!!!

LOCATING THE POWER SUPPLY PCB IN THE MIDDLE SHELF:
I measured the voltage at each end of the wire pairs going to the fans with a multi-meter and both pairs read 0 volts. Unplug the unit and remove the 4 middle shelf connectors. Next I took apart the middle shelf (remove the 4 screws) and removed a black rectangular cover that sits on a black rectangular box. Inside the box is the power supply PC board. There are 4 screws to remove the PC board from the middle shelf.

TROUBLESHOOTING AND REPAIR THE POWER SUPPLY PCB:
Once the PC board was removed I inspected the circuit board and found the S8050 NPN transistor that feeds the upper fan voltage fried. I checked the transistor and found the collector and emitter was shorted and base to emitter and base to collector voltage was not correct. Should be around .630 volts for a good transistor. There was also a 120VAC to 10VAC 400ma step-down transformer that read 0 volts on the secondary output terminals when it should read 10VAC. I unsoldered the transformer from the PC board and checked resistance on the primary winding which read infinite ohms. I took apart the transformer removing each e i lamination carefully https://www.google.com/search?q=transformer+e+i+lamination&espv=210&es_sm=91&source=lnms&tbm=isch&sa=X&ei=fVbLUovbJZHfoAT4m4CYAQ&ved=0CAkQ_AUoAQ&biw=1147&bih=627

Next I unwrapped the transformer tape and found a small thermal protector that read infinite ohms. I replaced the thermal protector and re-wrapped the transformer. Then replaced all the e i laminations and re-soldered the transformer back onto the PC board. I replaced the fan power supply capacitor as well which had some abnormal readings (12 ohms across the capacitor). There are two large radial capacitors of 1000uF 25V on the PC board. I located the fan power supply capacitor by following the copper traces on the PC board and replaced it. Pay attention to the polarity of the capacitor and when replacing it make sure you orientate the capacitor so its positive polarity aligns with the + symbol and the PC board silk screen.

REASSEMBLY:
I re-installed the PC board in the black box and reversed the steps I used for taking the middle shelf apart. I put the middle shelf back together and reconnected the fan wires to the fans. Plugged the wine cooler back in and this cleared my E3 E4 errors and unit is now working correctly. I think that the corroded fan connector shorted and this excessive current caused the transistor to burn up and short which then caused the thermal protector in the transformer to cut voltage off to the transformer.

Thank you, bobml3. My son came over and hard-wired the lower fan (sure enough, the white connector had come undone) and the thing is running beautifully. He used the little crimp-on connectors.

Great suggestion. I had the same issue with the E3 and E4 lights. Put new easy connectors on and works fine now. Reran the fan wires to the back of the separator panel and this gave me about 4-5 inches of wire to work with when making the new connection. left the connections exposed so if I have the problem again, I do not have to disconnect the other wires.

There are 4 connections on the RIGHT side of the shelf.

Once you've removed the two phillips screws on the shelf--slide it approximately 1/3 of the way out; marke the connectors (not necessary--but facilitates reassembly); and disconnect each of the 4 connectors.

At the back of the shelf--you will find the two (paired) leads that power the fans. Again--mark each (one is white, the other black). I believe the white connector powers the lower fan (hence my E4 code)--black the upper fan (most likely culprit if you have E3 code). The shelf will now completely slide out.

Cut one pair of wires at a time from the square connectors. Strip each wire, and crimp, solder or simply twist-n-tape the red-to red; black to black. Repeat for the other connector.

Reassemble.

I posted a short video showing how to fix it using the instruction from the other comments.

I haven\'t completely solved this yet - my upper section quit cooling more than a year ago, and I had an appliance guy out to look at something else and he said "the control system needs to be replaced" which is . Just followed this instruction and sure enough, the upper fan connection is corroded out - I just started getting the E3 error though even though the upper section hasn\'t been cooling for more than a year.

That said - here\'s a helpful hint - using a small, flat-blade screw driver, pop open the access panel on the front of the middle shelf. You can then easily disconnect the connectors that go through the right side of the fridge and then the shelf slides out very easily.

Instead of hardwiring it like others have suggested, I\'m going to put in automotive-grade connectors and then wrap them well with tape to protect them, and coat them with connector grease before I reconnect it. That way if I do have to replace a fan, it\'s an easier removal and I\'m not sacrificing any wire when I do so.