KichenAid/Whirlpool Range Burner Switch Replacement

For a few months now, one burner of our stove has not been working like it should.  My usual use of this burner is to turn it on the highest setting to get it to warm up, then move to the setting I want for the task, often to the medium setting.  The burner turns on high and then goes to medium normally, but when I try to adjust from a medium heat to a slightly higher heat, it stops heating altogether.

Here's the stove in question

Model KERS807SSS03

Since the heating coils turned on at all, I figured it was the switch that had gone bad and not the burner itself.  I found a video on YouTube that showed how to open the switch panel - fortunately mine is on the front of the unit, which makes it much easier.

First thing I did was to flip the circuit breaker to cut power to the unit.

When you open the oven door, there are two screws that need to be taken out, one on each end of the underside of the control panel.  With those removed, you can pull the bottom of the control panel out, then up to access the back side of the panel.

Right side screw to remove

With screws removed, pull out ...

... then up

It's not easy to know how hard to pull on this control panel to get it out of its mounting area.  It took a few yanks and pulls and grunts to get it.  But once it's free, you can turn it inside up to gain access to the switches.  I took the switch out to find the part number and ordered a part online.  Including tax and shipping, it was $133!  It probably cost the importers about $10 or less to get it from China.  Arrrg.  But there were some sellers charging $250 for the same part.  The seller I got it from was the cheapest I saw and on their website (as on most websites I looked at) there was a feature where you can enter your model number to determine whether the part you're ordering is the right one for the model.

Here's the inside of the left side of the panel

Pulling off the switch knob

Undo these two screws to free the switch inside the panel

The switch unplugs from the white and blue plugs

Here's the part number of the original

Putting in the new switch is just the reverse order of taking out the old one.  It went in easily and seems to be working perfectly.  Job's a good 'un!

But wait, there's more!  I thought I'd open up the old switch to see if I could tell what went wrong.  I'm not a circuit guy, so can't diagnose the electronics, but let's see what's going on in there.

It was easy enough to get the metal plate off, then the shaft comes straight out (with a spring around its lower end).  The shaft turns a round plastic piece that has four brass leads on its underside, and these leads slide on contacts that presumably change the amount of time the burner cycles on and off.  Is this a potentiometer - I'm not sure.

Metal plate off, shaft still in place

Shaft and spring removed, round plastic piece turned over

Close-up of above photo

I believe the four contacts on the underside of the round piece slide on the brass rings in the above picture.  Two slide in the non-continuous outer ring and two in the continuous inner ring.  The "off" position is at top in the pic.

If you look closely at the picture, you can see little piles of a greenish gel going around the rings.  I'm sure this is where the contacts push this gel as the knob is turned.  There was more of this gel around the spring.  I don't know if it just a lubricant, or if it is has anything to do with conductivity, so I don't know if it is supposed to be on these rings.  I ended up cleaning it off and put the thing back together.  Maybe I'll see if works better if another one goes on the blink, but for now, I don't feel like opening up the control panel again just to check.

Last thing here: on the back of this switch are the plug contacts, where the plugs from the control panel hook up with the switch.  Two of the prongs on one side appeared to have been burned a bit.  Could be nothing, but might also be the problem.

Back of the switch

The prong I'm pointing to and the prong in the foreground look burned at the tip

All for now.  If this helps someone, I'd love to hear about it in the comments.