Kenmore Smooth Top

[Biguglydude]

The "Element On" Indicator Light will not shut off.  It's on all the time.  All the burners and Oven elements are cold.  I checked the recall numbers and it does not seem to be involved.  To say the least I'm worried about this range turning itself on.  I've been looking for a service manual to better understand how this light is controlled.  Is it by FPGA (logic) or is it actually measuring current?  We keep the curcuit breaker open until we need to use it......

Model 790.9641440C

[JWWebster]

Here is how I would do it: Their are 5 wires on a standard top burner electric range control. 2 for line in, 2 for burner and one small one to that pilot or surface on light.
I would find the small wire on each switch and remove them one at the time till that light went away. Then I would replace that particular switch. Post your correct model number and I could get ye the exactamundo.

[Repair-man]

This is not a "standard cooktop", it is a smoothtop with radiant elements...
On this series, the Hot indicator is generated from 2 contacts on the radiant element. The smooth top would have to be lifted off and each element checked to see which  one has stuck contacts. Each of these elements has a thermostat bar across the top of the element which turns on the indicator light when it has reached a certain temperature. One of them is stuck closed, and can be detected with your OHM meter. The diagram for your  cooktop is stuck underneath the outer cover and it will show the ciruitry.

[JWWebster]

Yeah I have seen that. Ain't no way to repair those burners either.

[Biguglydude]

   Cool!  I'll look for the diagram and get back with you.

Thanks Guys!

[Repair-man]

If you'll kindly look under the unit and get the whole model number instead of a partial, things will go much better. By the 3-digit prefix, we can tell it is made by Frigidaire.

[Biguglydude]

Model # 790.9641440C
S/N  VF82219775

[Repair-man]

Much bettah! Here's your diagram...

Cooktop Wiring Diagram

Test each element with your OHM meer, terminals 1b to 2b, and see which one is closed. Thats going to be the bad element. Be sure to disconnect power to the unit first.

[JWWebster]

Wow those burners are pretty dang spensive

[Repair-man]

So is a new cooktop, Tonto

[JWWebster]

Say he didn't want to pop fer a new burner right now, could he just ohm out each burner till he finds the one with continuity on the temp probe and just tape off the indicator wire?

[Repair-man]

Only if he wanted himself or a child to get burned not knowing the top was hot...think with your dipstick, Jimmy

[JWWebster]

Hay if you don't ask you never find out right. gee I wonder what they did before ralph nader.

[JWWebster]

Hay Big let me know which one it is and I will give you a good link to a decent price.

[Biguglydude]

OK guys, I goterdone!

According to the wiring diagram (316441485) the "Element On" light on the panel is listed as the "Surface Indicator".  So, I found the surface indicator is controlled by two steering diodes located on the Simmer Select Board.  Both diodes measured good.  At this point I figured I need to find out witch circuit is sending the 110v.  So I powered it up and found the P1(2) was giving me the 110v (Left Surface Unit).  The P connector on the left surface control drives this line and was always 110v (switch on or off).  This wire also goes to the cooktop lockout board.  This looks like an input line because it drives the anode of a another steering diode.  So I disconnected the purple wire from the P contact of the switch and the light went out.  The P contact remains 110v no matter if the switch is on or off (looks like a sore thumb here).  So I unplugged the stove and moved to the Ohm meter.  The L1, H1, and P connector all measure 0 Ohms no matter if the switch on or off.  I measured the other surface switch in that housing (L2, H2) and that contact is working OK.  So it looks like the coil was turning off but only by one side.  I need to replace the switch. 

This sure sounds like it should have been part of the recall.  If both of these switches would have shorted the element would have come on!  Does anyone know the part number of the recalled switch in question?