Miele W1918 washer will not drain

[Vladimir]

I have owned this washer since I bought it new in 1999. Up until last week I had exactly zero issues with it. That's 18 years of trouble-free operation. This washer has survived three moves, including two long distance out of state moves. Last week during the wash cycle a red light indicating a drain problem came on and the water did not drain from the load of laundry I was doing. I could not hear the drain pump motor running. I drained the machine manually and tried to find info online about this problem. Unfortunately, I could not find anything at all about this. So I downloaded a service manual that Miele provides and set about troubleshooting the problem myself. I am an electrical engineer by education and software engineer by profession, so I am not intimidated by electronics. I started by measuring the resistance of the drain pump motor. If it measured as open circuit or short circuit it would indicate a bad motor. Alas, the motor measured something around 4 ohms, which seemed normal to me. So started checking for power going to the motor. I connected my voltmeter to the motor supply wire and put the washer into a drain cycle. This washer can be put into any of the available cycle components by user controls. I can select spin, drain or rinse from the front panel. So I selected drain and my voltmeter read nothing from the drain pump motor feed. Miele makes access to the internals of the machine very simple. Three 10mm bolts around the tub opening and two screws in the soap dispenser area and the whole front including the washer door swings open on a hinge to the right. This machine has two circuit boards mounted to the front sheet metal. A logic board up top and a power control board down on the bottom. They are connected by a ribbon cable. I traced the drain pump motor wire to the lower power board and put my voltmeter there. No power coming from the power board to the drain pump. At this point I could say that the problem is either in the power board or the logic board that issues commands to the power board. My money was on the power board since that is what does all the heavy lifting of operating the pump. It has a bunch of relays on it that switch the power on and off to the various motors in the machine. I went ahead and removed the power board from the machine. Miele made that very easy. A few plastic clips that could be released with a screw driver and board was off. I unplugged all the connectors and took a good look at the board all over. Immediately, I saw a printed trace on the board that looked suspicious. Traces on the board are wires that carry electricity to various places. The trace in question went from a relay to a via, which is a special hole in the board that carries the trace over to the other side. On the other side the trace also looked suspicious and continued from the via to the connector that supplies the drain pump motor with power. I had my problem right there in plain sight. The trace is a thin layer of copper bonded to the circuit board and covered with a silk screen (green in this case). The green of the silkscreen was completely gone from that particular trace (on both sides) and the copper looked like it was no longer bonded to the board, but rather floating above it. I checked for continuity from one end of the trace to the other and got an open circuit. This was the problem. Over the years the current running along the trace has heated it up repeatedly (possibly due to a design flaw that under sized this trace or maybe because the drain pump struggled against some clogs in the past) and finally repeated heating and cooling of the trace caused it to fail. The fix was very simple. I simple removed the damaged trace from the board since it was just hanging there not really attached to anything. Then I ran a fairly thick 14 gauge wire to replace the trace. This required a little soldering. I reassembled everything and now my washer is running like new again.

I hope this helps some one in the future. If more details are needed, please contact me. I'll be happy to help.

 

[Richelle]

My machine did the exact same thing. Thanks to this post, I knew what to look for. It was the same problem. With a basic knowledge of electronics, some skill with a soldering iron, and this post as a guide, I had no problem at all fixing what would have otherwise been an expensive service visit. Thank you Vladimir!!!

[mellowmaximo]

I tested the pump for continuity across it's two prong socket .  good signal.

Tested the red pump wire going to power board: good continuity.

I am seeing 88 volts when washer set to drain cycle at the connector wire going into the pump.  The pump is a 120v pump 90 watts 60hz... 

I looked the power board over as you suggested Vladimir but it looks in good order.  no burns, swollen, or black areas.

[mellowmaximo]

Solved: washer needed neutral wire at 220 connector.  220 does not require neutral, but components of washing machine that run on 110-120v, such as the water pump, need neutral to function.