Jenn-Air (Whirlpool) JGS9900BDS oven or broiler causing controller to reset

[Keyslammer]

Model Number

JGS9900BDS

Brand

Jenn-Air

Age

More than 10 years

Symptom: Selecting either the oven or the broiler (temp/level does not matter) - the controller says "Warming", the igniter glows (heats up), the burner ignites for about 3 seconds and the temp starts to come up and then the controller suddenly and completely resets (requiring me to power cycle the oven and reset the controller). When this happens, the display only shows the time-clock and none of the keypad inputs for the oven do anything (including CANCEL or ENTER, etc). The words "Power Fail" do not show up until I physically unplug and replug in the oven to reset the controller.

Operation and Tests Performed:
-The stove top burners work fine
-LP gas pressure is correct (0.4 psi)
-The oven igniter was replaced with fresh igniter that measures 160 ohms cold (no change)
-Oven temp sensor rod replaced (no change)
-Oven Controller swapped out with a NEW controller (no change!) - at this point I was almost certain it was the controller, nope.
-Range cooling fan tested with 115V (working fine)
-The High Temp thermal switch was bypassed with a jumper wire (thinking that might be the source of the apparent reset or power loss to the controller, no change)
-I measured the gas dual valve inputs (bake and broil both measure under 2 ohms)
-I disconnected the gas valve inputs (as a check), and the igniter did not glow (expected), but after about 10 seconds, the controller reset again...same symptom. I had to power cycle the oven to reset the controller.

At this point I am at a loss as to the cause of this problem or what I should be checking next. There is no "flame sensor" and I do not see any input to the controller that would cause it to perform a complete reset, shutting down the oven. It is interesting that the burner continues to operate for about one second after the controller resets itself. The reset is an abnormal condition (requiring me to power cycle the oven). I think I will need feedback from someone that really knows this appliance or has seen something like this before. I can provide the complete wiring diagram if needed.

 

[Dan O.]

the controller suddenly and completely resets (requiring me to power cycle the oven and reset the controller).

I don't see anything that could cause that besides a problem in the electronic control itself.

LINK > JGS9900BDS Electronic Control Board

There is a high-limit safety thermostat in the circuit that could stop power to the control but that should result in the "Power Fail" message as should any other power interruption to the control. There are no external factors I know of that could cause what you described, only a malfunction of the control itself.


Dan O.

 

[Keyslammer]

Dan,
That's what I would have expected (replacing the controller). However, after swapping out the controller with a new one, the problem remained. I've learned a few more things, I don't even have to run an oven or broil cycle. I can just turn on the Jenn-Air vent (or just about anything else) and after 6 seconds or so, the controller resets. So this isn't a "current draw" issue with the igniters or the gas valve. The ONLY common denominator at this point is the keypad itself. So I ran a test where I turned on the Jenn-Air vent and DISCONNECTED the keypad cable entirely...the controller still did a reset. Upon power cycling the oven, I went through each key on the keypad to check for a "beep" (no apparent issues). I measured the AC power at the controller and it never varied more than a volt or two from 118V when the oven did the 'reset'. I even tried disconnecting various sensor inputs to see if the behavior remained. I did get a few oddball error codes, but after a 6 seconds (poof) controller reset. Now why would this SAME behavior occur with two different controllers? I am beginning to wonder if there isn't a "common problem" with these controllers and I happened to get a replacement that exhibits the same problem??

Regarding the high-limit safety switch - you are right, that would show a power fail (since it turns off AC LINE to the controller and a few other items). Regardless, I BYPASSED that switch just to be sure there wasn't a 'glitch' with that input. No joy (so I put it back in-circuit).

sigh...

 

[Dan O.]

Now why would this SAME behavior occur with two different controllers? I am beginning to wonder if there isn't a "common problem" with these controllers and I happened to get a replacement that exhibits the same problem??

Was the replacement control brand new? If "new", i would say there is likely an external cause although I can't imagine what that external factor might be. If it was a used control, it is possible they both suffer a common affliction.

I'll try to look at the wiring diagram when I get a chance to see if anything catches my eye.

Dan O.

 

[Dan O.]

A couple of people have reported similar problems caused by the meat probe socket (not temperature sensor) in their ovens, shorting. I don't know why. Both were different brands than yours and each other, so don't know if it would be possible in yours as well.

Unfortunately that socket can't just be disconnected as it looks like it's connected in the same wiring harness as the oven temperature sensor which if disconnected, would definitely cause an error to display.

If you can get to the socket, the wiring might be able to be unplugged from it to test the hypothesis? I believe this is the meat probe socket on your model. I don't know exactly where it is located.

LINK > Meat Probe Socket


Dan O.