Need appliance parts? Call 877-803-7957 now or use the parts search box:

Parts Search

Learn appliance repair at online the Master Samurai Tech Academy.  Learn more.  Earn more.

FAQs | Repair Videos | Academy | Newsletter | Podcast | Contact

skintdigit

Whirlpool modular ice maker thermal fuse on black wire in harness

12 posts in this topic

What makes 'em fry?

Yes, I know.....heat. But why does the mold get hot enough to open the fuse? Could leaving the IM on with water supply shut off do this? Or does it usually point to a problem with the module?

SD

Share this post


Link to post
Share on other sites

Need appliance parts? Call 877-803-7957 now!

It's a good question. My theory is that it has to do with a corroded/loose connection inside the module or at the wire harness connector. Loose connections make heat but also increase current draw an the fuse may open in response to that. Would be interested if anyone else has any thoughts.

Share this post


Link to post
Share on other sites

Happy Fourth of July!

Looking at the wiring and timing contacts...what would happen if the motor gave up the ghost shortly after a harvest cycle started? Would the mold heater element then remain energized until something happened to interrupt current to the IM(owner turns off the unit or mold gets hot enough to open the thermal fuse)?

SD

Share this post


Link to post
Share on other sites


Makes sense that this fuse is designed to blow if heater is stuck on during a stalled cycle. Excerpt from above manual:

The thermo-fuse is spliced into the black wire of the
ice maker wiring harness. It is a 170° F non-resettable
fuse. A no ice complaint could be caused by excessive
heat. Replacing only the wiring harness will only
temporarily solve the complaint. The ice maker
thermostat should also be replaced.
NOTE' Currently wiring diagrams do not show the
thermo-fuse.

Share this post


Link to post
Share on other sites

A bad IceMaker can cause it to stop or jam.

Share this post


Link to post
Share on other sites

Thanks, folks.

New icemaker installed, jumpered T to H to initiate harvest. Removed jumper wire after about 10 seconds of motor run and the IM continues to complete cycle. Only problem....no water at end of cycle. Checked voltage both at fill valve(between brown wire and ground) and at IM test ports between V and N. Voltage during 7 second fill time is only 6 volts both places. I have 120 to IM.

Ideas?

SD

Share this post


Link to post
Share on other sites

check for Water Valve shorted ?

then check voltages:

L to N

H to N

T to N

pagefrom4316835indoorim.jpg

Share this post


Link to post
Share on other sites

Belated thanks, RegUS. I finally got back to looking into the icemaker no-fill problem. I knew the old IM was fried...no continuity at the thermal fuse on the black wire(toasted thermal fuse) and direct wire jumpering the drive motor after opening up the module showed that it was also fubar. OK, so the drive motor quit and caused the mold heater to remain energized for a period of time until the mold got hot enough to open the thermal fuse. Made sense to me...new icemaker should solve the problem, right?

Not so fast, bunky.

When I installed the new IM and started a harvest cycle all was good, but no water fill at the end of the cycle. :confused:

Resolution is that the solenoid was shorted on the water valve. Resistance of coil is 3 paltry ohms, resistance of neighboring water-in-the door coil is 269 ohms, and I know that one is functional. Verified by attaching IM connector to the door water solenoid and running a harvest cycle. Sure enough, water flowed from the door water dispenser for 7 seconds, give or take.

Revised theory....water valve coil gave up the ghost, which caused the old IM to cycle almost continuouslyI(no water in it to slow the cooling of the mold and the closing of the thermostat). Eventually the drive motor quit and then the mold overheated and cooked the thermal fuse.

That's my story and I'm sticking to it. :moondance:

SD

1 person likes this

Share this post


Link to post
Share on other sites

Going to put your theory to the test. Two ice maker thermal fuses blew while harvester in the 12 o'clock position. If the water valve is bad, then you may be on to something... continual cycling since the thermostat never warms..... interesting.

Share this post


Link to post
Share on other sites

A shorted mold heater will interfere with voltage supplied to the inlet valve solenoid and if the heater shorts to the point that it blows the thermal fuse in the harness it can take out the valve as well.  Most common cause of a shorted heater is a leak through the Teflon coating of the mold.  I recall the older GE heat release icemakers that produced the round cubes.  That icemaker did not have a thermal fuse so when the ejector got jammed during harvest (usually due to a bad shaft seal), the mold heater stayed on, damaging the freezer liner.

Share this post


Link to post
Share on other sites

If you left the jumper in for ten seconds you left it in too long and it will not fill with water. You should only leave it in until you hear a faint 'click', then remove it, about 3 or 4 seconds. If you leave it I longer it will not fill with water because the module thinks the bimetal is still closed. If you installed a new IceMaker it's not going to have a short or any of the same problems that the old one may have had internally. I think you just left the jumper in too long. Try it again.

1 person likes this

Share this post


Link to post
Share on other sites