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Here are tech sheets
https://www.servicematters.com/d...0Sheet%20-%209754365.pdf

https://www.servicematters.com/d...0Sheet%20-%209754373.pdf

First as always check for power going into the unit
L1 to L2 = 240
L1 to Neutral and L2 to Neutral = 120

May be best then to get in a pro!!!
Especially since a stove is 240 volts, which is very dangerous!!!

Everything else seems to work fine, the oven, lights, screen, keypad.
OK, just to explain a little
The power into the unit is 240 volts, it is made up of two 120 volt supplies.
Your above items all run off of one of the 120 volt supplies.
The burners/elements run on 240 volts.
That is why it is important to check the input power as it sound like you are not getting 240 volts to your elements.

I find electronics to be very interesting.
If you are willing to invest some time most of it is not that complicated.
There is a lot of basic electrical info available on the web.
First I would learn what AC volts, DC volts, amps and ohms are and how they relate to each other.

I want to try to tinker with it although I wouldn`t want to zap myself with 240V by sticking the voltage meter's test leads into the wrong place!!
I did not mean to scare you off but wanted to let you know about the danger so that you use extra care.

If you can provide any additional pointers they`d be greatly appreciated.
I would turn the breaker off/on slowly a couple times. Sometimes you can loose one side of the line without actually tripping the breaker.

If you want to go further I would suggest you purchase a meter. 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. It will allow you to measure voltage and resistance.
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.

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

Here is a good site with info on oven repair
http://www.applianceaid.com/erange.html

Congratulations on finding the problem!!!

(actually the meter gave me 125 and 248 - these values normal?).
Yes, looks like you have good power.

Do you think I need to also replace the suppressor?
You have a varistor and two capacitors. You cannot really check it with a meter since to check it properly you must use the operating voltage and you meter is low voltage. I would remove it and check it visually for damage. They do not go very often.The best you can do is check to see that it is not a dead short (0 ohms). That said it may not be a bad idea to replace it.

Should I buy new ones to replace them or can I snip the ends and buy new metal crimp attachments?
You can snip the ends and buy new crimp on connectors. You will have to snip them back till you get to nice clean (bright copper wire). So it will depend if the wires are long enough. If they do not have them here you can get them at Home Depot etc. Just make sure you get ones that are for high current.
I will forward this attention this sites administrator re: parts.

If they should be replaced where can I buy these wires as I cannot find them on AP's parts website.
I will forward this attention this sites administrator re: parts.

Also, any ideas on what may have caused this?
Check from Neutral to red with your meter. With all elements off it should be high resistance. Just a check that nothing in the stove itself caused this.
It may have started from day one. What happens is that if the connection is not perfect (0 ohms), it has a little resistance. This resistance acts like a heater when current passes through it. The connection heats up which causes corrosion and micro-arcing. This increases the resistance which increases the heating and so on and so on till the connection fails

How can I stop this from happening again?
Make sure you have a good connection. Clean the black wire side connectors with some very fine emery cloth or sand paper just so it does not do it on this side in the future. You can get some contact goop, it is commonly used to coat aluminum wires to prevent corrosion but works with all wire types (Home Depot etc.). A very light coating on the connections will reduce heat/corrosion problems. Since it does conduct electricity you do not want to go crazy with it as it could short between the connections if you use too much.
With the unit unplugged and once you get back to good wiring you can check from each side to Neutral with your meter while turning the each of stove top elements on (one at a time). You should see fairly low resistances 10 to 30 ohms but not dead shorts (0 ohms). Unforetunately you cannot check the oven elements as you need power for the control board.
Once you get it all redone, plug the unit in and check that the power is good L1 and L2 to Neutral and L1 to L2 at the terminal block with different elements on. Here is where the extra caution comes in as we are messing with 240 volts. Expect that the voltage will drop somewhat with an element turned on. The L1 and L2 should be close to each other.
For instance if L1 to Neutral is 240 volts and L2 to Neutral is 220 volts then odds are high that there is a problem as the L2 side is pulling a lot more power than L1 side and this is dropping the voltage.

Lastly, I`m replacing the ceran cooktop since the current one is very old, worn, and seems to be cracking. Do I need any additional parts when changing that (like gaskets?etc...) or can I just swap it out and use the existing hardware.
I do not think you should need more parts. Would not be a bad idea to open it up before ordering parts and inspecting the elements etc. Then you can get every thing you need at once.

Hope the above helps.
Others will probably take a look at this and hopefully add anything they feel I have missed or made a mistake on. There are some darn good techs who hang out at this site.