Here are your parts
Parts for Maytag MER6770AAW Range - AppliancePartsPros.com

Here is a link to a service manual.
You will have to join the site and be logged in to be able to download it.
http://appliancejunk.com...wnloads;sa=view;down=390

Looks like a oven sensor error.
Check the sensor with a meter.
Should be around 1100 degrees at room temperature.
If not replace it.

If OK then it is probably a control board problem.

[COLOR="Blue"]It started with the upper Oven then the lower Oven the next day... so both sensors? [/COLOR]
This sounds more like a control board problem as it is unlikely that both sensors would go bad at the same time.

Try turning the breaker off for a couple minutes just to see what happens re: does it reset etc.
[COLOR="Blue"]
What kind of meter do I need to have to test that? I have a small volt meter...[/COLOR]
If the meter has a resistance scale that measures from 0 to 2000 ohms or higher it should do the job.
Below is a link to info on doing this.
Check out 7, 8, 20 and 21.
http://www.applianceaid.com/ele...-range-repair-topics.php

Also my usual blurb on meter usage follows.
If you do not own a meter, I would suggest you purchase a one. You can get a decent digital multimeter for under $20.00. You do not need fancy though it is nice if the leads are a couple feet long.
If it saves ordering one unnecessary part it has paid for itself and you end up owning a useful tool.
Most places will not let you return electrical parts so if you order it, you own it.
A couple things to watch when measuring ohms and continuity
1. Always remove power from the machine otherwise you could blow your meter.
2. Always disconnect at least one side of any device you are checking. This eliminates the possibility of measuring an alternate/parallel circuit path.
3. When checking for closed contacts and continuity use the lowest scale (Usually 200 ohms). Then try higher scales. This scale is 0 to 200 ohms so if the device you are measuring is 300 ohms this scale would show an open circuit which it is not, you are just measuring outside the scale's dynamic range.
4. When you start always short the meter leads together. This will tell you that the meter is working and if there is any 0 offset.

There is a good STICKY at the start of this forum about it's use.

I am not sure.
Could be that an error like this will shut down both ovens.

I would start by checking the sensor.