Its just a simple 2 slice toaster, but this one really has me beat.
The lever does not lock down, even though the elements turn on.
I tried all the simple fixes of cleaning the gap and the oxidation off the contacts.
Have drawn a schematic to get a better understanding of the circuit.
Already swapped out the capacitor and the Zener diode. Also tried swapping the 10V line from the elements.
The connector goes to another board with potentiometer and 3 LEDs and switches, but have yet to draw up that circuit.

 

Welcome to AAC!
Have you tested the solenoid coil for continuity?

 

Does the solenoid pull in when the lever is pressed?

I had that failure with a toaster, and the problem was, the solenoid was not holding the contacts closed after the lever was released.
I had to bend the contacts so they remained closed with the solenoid energized.

 

I had one to repair many moons ago.
Same symptoms.
The young person who brought it to me, said it was broken.
I had a piece of wood the size of a slice of bread that was used for testing toasters.
It worked perfectly with the dummy bread/wood. Job done!

 

Welcome to AAC!
Have you tested the solenoid coil for continuity?

Not yet, as I think it will need to removed from the circuit to test properly.
Also, when the fault first manifested, the solenoid did hold once the elements warmed up by manually holding the lever down for a minute or so.

 

Also, when the fault first manifested, the solenoid did hold once the elements warmed up by manually holding the lever down for a minute or so.

That rather indicates you may have the same failure I noted in post #3.

 

This is a common problem. Examine the contacts and the rivets and connections that are related to the contacts.

 

That rather indicates you may have the same failure I noted in post #3.

The solenoid is designed to hold the lever down once contact is made(via metal plate in a hinged small latch) . The elements turn on, so contact is being made and remains on as long as lever is held down manually.
It appeared that the solenoid was not getting enough current as it would turn on once the elements heated up, by holding the lever down manually for a minute or more.
So, I swapped lead to power to the coil to the connector coming off the middle elements and this caused the 50-ohm resistor to burnout, (twice !!).
I have no idea why.

 

Is the 10v power supply wire connection, for the coil and other circuit board, a riveted connection directly to the heating element itself?
Could the rivet-to-element connection have deteriorated with the heat cycles?