Canister vacuum keeps turning off, can push buttons on wand handle to restart but shuts off again as soon as you start to move handle

You might have an obstruction somewhere or something is keeping a valve that directs the airflow from the floor to the wand from moving properly. You will need to investigate all these areas to determine what is nor operating properly.

The spark may have wiped out the programming in the microprocessor. Probably needs to be re-flashed.

pull up extension wand. remove the wand part by pressing the gray button near the bottom of the wand.
remove canister.
if your looking at the front of the vacuum where the canister was near wher the clear bin of the canister would sit there is a gray push button. it is kind of hidden so you have to keep an eye out for it
but when you find it push it in and pull up on the hose and it will come off the vacuum.

either the reset is bad or the motor is drawing too many amps and tripping the reset. Do you have an amp meter? Check the amps being pulled by the wand attatchment against the load recommended by the manufature, this is usually located on a plate somewhere either on the wand or the canister.

Depending on the age of your 2100, you will need to replace, the wand cord, the handle wiring and perhaps theh upper wand inner tube and handle as well.
If you examine your cord contacts they will be blackened from slippage, so will the female socket they plug into. On and aging 2100 the 1/2 inch groove at the front of the chrome handle tube begins to wear and the metal inner tube clip under the thumb button of the wand develops play back and forth. The wand comes apart into 4 pieces, plastic sheath, upper and lower tubes and cord assy.
If the hose handle groove is worn enough to allow in and out play, you will need to replace the handle, it's wiring, and at least the clip button on the upper wand as well as the wand cord.
You will find these wand parts at a pro vacuum shop but if your hose is original you will need to go to an AERUS Electrolux repair center for parts.
Post back with your results.

The vac very likely has a thermostat located near the suction motor that will stop the motor to keep it from burning itself out. These thermostats rarely go bad. You need to look for a blockage starting with the power nozzel (carpet sweeper) all the way to the canister. Take the hose from the canister and power nozzel and drop a coin in one side and see if it comes out the other end. If not, try pushing a broom stick thru to move the blockage to the other end and get it out with needle nose plyers. Don't use a coat hanger!
You can take the carpet sweeper loose from the wands and look into the elbow (part that swivels) for a blockage. It all has to do with air flow to keep the motor cool.
Joe

You may not have power to the power head. Check the plug at the neck of the power head, also the wand connections to make sure they aren't burnt. Most of these powerheads also have a circuit breaker on the top of it, press it to see if it will re-set. At the end of the hose handle, there is a female plug where the wand plugs into, push it ans see if it will move inward or not. If it does, then it has broken loose inside of the handle and isn't allowing a connection to the wand. The switch on the hose handle may be bad. The power head motor could be bad. These are the most common problems when the power head won't run.

Open up the power head and check the toothed corners where the power head sits - it sounds like thread has caught up at the sides which can only be removed by opening up the powerhead to clean it.

Check the plug ends at the top of the wand and the plug going into the hose handle, also at the bottom of the wand. It sounds like they may be burnt, if so they will need to be replaced. One cause of these connections going bad is not turning the power head off when connecting or disconnecting. Therre are other causes, the switch in the handle is going bad, also some of these cannisters have a relay mounted by the vac motor, sometimes they go bad.

Some of these has a reset button to push on the powerhead. Check the plug at the end of the hose handle, is it pushed in, if you push on it and it goes further in, then the tube in the handle will have to be replaced, the holding tab broke off of the tube. Pull the wand off and look at the prongs to see if they are burnt. it they are, then that power cord will have to replace as well as the want.