I have the Jenn-Air black top cook top model number JEC8430 or 8536 either way I can't see the numbers around the knobs...are they suppose to light up? If not, that is without a doubt the most horrible design ever. I am certain the salesman told us they did.

SOURCE: Jenn Aire Cook top

Here's a link for Jenn Aire parts dept. There's a toll free number that you can call and I'm sure they will be able to help you find replacement knobs and the glass top.
http://www.jennair.com/content.jsp?name=parts_stores

SOURCE: Jenn-Air electric stove top - burners/fan won't come on

I had the same problem. Went to an appliance store that carries Jenn Air. Replaced both plug in units. Now they work perfectly and it cost less than $350 total! Good Luck!

SOURCE: jenn air cook top

Yes you can. Call Jenn Air ((877) 232-6771) and give them your model number (serial is helpful too). They sent my replacement glass within a week. I have a model JED8430ABD from 2000 and they had the top. Fit perfectly and took about an hour to replace.

To change it out, after unplugging the cooktop, I removed the metal tape connecting the external vent shaft to the blower. Then I just lifted the entire cooktop out up out of the countertop so I could access the screws on the sides of the cooktop (looking at the edges of the new cooktop glass helped me figure out which screws to remove around the edge). Then I removed the 2 screws in the vent area on top (1 black screw on each side). And that released the cooktop glass from the metal box that holds the burners. I then took the rubber rings out of the knob holes so I could put them in the new cooktop (I almost missed that...). Finally, I put the new cooktop glass on, put the screws back in, lowered the cooktop back into the counter, and retaped the blower to the vent shaft. Voila!

I really wouldn't be afraid of doing this yourself if you are handy at all. And it will save you a ton. Good luck.

PS The screws around the perimeter are hexigon shapped, so you can't just use a screwdriver. I found my Black & Decker electric screwdriver had that same shaped hole that it held the bit, so I just pulled out the bit and used the screwdriver that way. Worked like a charm.

SOURCE: Water boiled over into control knobs for the cook top elements.

Just fixed this problem and repaired the corner of the Ceran cooktop.

Disclaimer: These cooktops run on 220V and will kill you if you don't know how to work with electricity. If you're unsure, get some help.

The boiling water slopped out of your pot, and went over to your controls (knobs) and went down the shaft and into a component call "Infinity Switch". The water caused the switch internally to weld one of the two internal sets of contact points into a permanent position. The fix is to replace the
"Infinity Switch" that the boiling water spilled into. The Infinity switch is the component that the control knob slides on to.

In my cooktop one of the infinity switches failed and appears to damage the adjacent switch. Mine actually caught on fire and damaged the wiring and the connector. Hopefully you are better off. Since they were in such close proximity I replaced them both. For $20 you might consider the same. I replaced both to be safe and they were $21.47 each.

My cooktop has 4 elements 2 small, 1 large and 1 combined (small and large) surface. A large element was definitely damaged and possibly a small element. I ordered both. I mention this in case a multi-element was damaged on your cooktop.

You will need to contact either Jenn-Air or someone. Since you can't see an exploded parts list online, you'll have to use the schematic. It is in a plastic sleeve and it stuck to the side of the ventilator housing underneath the cooktop.

When you wire the new part in, make sure you have the wiring correct or when you turn it back on you will burn up the new part.

I hope this helps.

SOURCE: Jenn-Air Cooktop replacement needed

You can get a new cooktop surface from Maytag/Jennair for $229. It is a pain however to replace it. Where is the crack in your cooktop and does that crack pass directly through a heating element? If not, then you may be able to repair it. I broke the corner off mine, and then dropped the piece (now 5 pieces). I was able to bond them back together and you really can't tell it was ever broken. But, it takes some work.