Cuisinart Toaster Toasting One Side

This was a failed attempt to fix my neighbor's four-slice toaster.  The problem was that for each pair of bread slots, only the outside elements toasted properly.  That is, for the left two slots, only the left side of the left slice of bread and the right side of the right slice of bread got toasted.  The same was true for the right side two slots.  On both left and right pairs, the inside heating elements did glow, indicating that electricity was flowing, but the glow was far less than for the outside elements.

The Appliance: Cuisinart Toaster, model no. CPT-180

The unit has separate controls for the left side (two slices) and right side (two slices).  Each side has a standard dial to control the darkness of toasting.  Each side has selector buttons for bagel mode, defrost mode and reheat mode (each with an indicator LED light), as well as a cancel button that will pop the toast up at any time during a cycle.

Front view

Top front view

Info on bottom of unit

The Problem: Not toasting the same on each side of a slice of bread

My current toaster has similar mode switches.  When bagel mode is used, it is the inside heating elements that heat more and the outside less.  That is, the right element of the left slot and the left element of the right slot glow brighter than the other elements.  The subject toaster seems to be stuck on a mode where the opposite is true.  If a bagel were placed in the left two slots with the cut surfaces facing each other, only the crust side would get toasted.  The Cuisinart manual states that in bagel mode, both sides toast equally, but for longer than on standard toast setting.  This is different from how bagel mode usually works.

Right two slots shown.  Outside elements glowing.

Moving the camera over a bit, we see the right inside element
not glowing (it actually is glowing, but far less than the outside elements).

Disassembly

First, there are four screws, one at each corner of the bottom that allow the body to come off the base.

Bottom view, pointing to one of the four screws

Before removing the upper body, one must remove the two levers that press the toast down.  If you look inside the slot for these levers, you can see a small white plastic clip that holds the levers in place.  The clip needs to be moved slightly to pull out the lever.  Note that the toast darkness knob does not need to be removed.

Tough to get a good picture here - looking through the slot the lever rides along.
Yellow arrow points to the receiver that the shank of the lever goes into.
Red arrow shows the small clip that holds the lever in place - it needs to be
pushed down to release the lever.

With the upper case removed, you can see where the lever is inserted
(yellow arrow) and the little clip (red arrow) that keeps it from pulling out.

After pulling the top of the toaster up and away from the base, we need to undo two plugs that attach the front controls to the base.

Upper case is removed, but still attached to base.  Pencil pointing to one of two plugs.

After plugs detached, the top comes free.

I also disassembled one of the circuit boards that control the bagel/defrost/reheat/cancel buttons as well as the toast darkness knob.  I really don't know what I'm doing with circuit boards, but it's good to look to see if anything obvious is wrong - like detached connections, burned components, etc.

Four screws held this board in place.  You can see the potentiometer that the 
darkness dial turns (bottom), as well as the four buttons that control bagel, defrost,
reheat and cancel settings.  The red things are LED indicators for those modes. 

Diagnosing the Problem

A very common problem with toasters is that crud gets in the way of the press-down-to-start-toaster lever.  The lever not only moves the bread down into toasting position, but it also starts power to the heating elements.  But one little known thing is that the lever stays down by means of an electromagnet.  When power is removed using the cancel button (or by unplugging the appliance from a wall socket), the toast pops up.

Pointing to the lever for the right pair of slots

Note these four contacts

As the lever is pressed down, the white piece forces together the left two
and the right two contacts.  This starts electricity flowing and an electromagnet
is created that will hold the lever down.

This next series of pics shows a side view of the lever coming down.
Lever not yet seen.

lever coming down ...

... and down further ...

... and just a little further until the two plastic clips engage and
an electromagnet is created (just below the clips) to keep the lever down.

For many toasters, crumbs or raisins or other debris get caught in places they shouldn't and get in the way of the electromagnet doing it's job.  So sometimes a simple cleaning will fix a toaster.

Unfortunately, this toaster doesn't have that problem.  I suspect it's something to do with the circuit boards.  I don't see anything obviously wrong on them.  But even if I did, both left and right boards behave the same way.  It would be a real coincidence for both sides to have the same problem.

I'm stumped on this one.  Unless I get a comment soon about how to fix this, I'm going to chop it up for parts.