Vacuum turns on for 2 sec and then shuts down, full bag light on , but bag is new

This was an answer given from Thomas on Fixya 5 years ago for this same problem:
"Electrolux uses a pressure differential control valve. This valve measures air before and after the bag. There is a orifice or small hole where the hose connects to the vacuum cleaner, and a orifice at the back of the bag canister. As the bag fills up the suction pressure reduces at the hose connection and increases at back of the bag canister. When this happens the control valve has a diaphragm that closes, which shuts the vacuum off and gives you a full bag light. There is a thin plastic flange that prevents an o ring on the control valve stem from coming off. The flange breaks, the o rings comes off the stem and the vacuum will shut down indicating bag full. The after market price is about 22.00. The valve is easy to replace if you are familiar on electrolux vacuums. When I replace these valves, I use epoxy two part plastic putty on the flange of the valve. It takes 2 days to cure, but the flange will not break."

Another person responded for the series 6000 (which may not be applicable to your 7000):
"Turn the knob on the top of the vacuum all the way to the right.I had the same problem and that fixed it."

Good luck on your troubleshooting.
Let me know if this was helpful...

Electrolux uses a pressure differential control valve. This valve measures air before and after the bag. There is a orfice or small hole where the hose connects to the vacuum cleaner, and a orice at the back of the bag canister. As the bag fills up the suction pressure reduces at the hose connection and increases at back of the bag canister. When this happens the control valve has a diaphram that closes, which shuts the vacuum off and gives you a full bag light. There is a thin plastic flange that prevents an o ring on the control valve stem from coming off. The flange breaks, the o rings comes off the stem and the vacuum will shut down indicatiing bag full. The after market price is about 22.00. The valve is easy to replace if you are familiar on electrolux vacuums. When I replace these valves, I use epoxy two part plastic putty on the flange of the valve. It takes 2 days to cure, but the flange will not break.

You have a Electrolux, not a Guardian though, right? The light you are talking about is the bag full indicator. I know your bag is not full, so, try this. The knob on the top of the cleaner is a fine adjustment designed to let the bag fill up in different conditions, (dirt types) . So...turn the dial down to setting 2. Try it again. Did it work? If so, this is your adjustment . No need to ever adjust it agin. It is NOT the suction control. If this did not fix ya (haha) then, your adjustment diaphragm is bad and you will have to break down and bring it to Aerus(Electrolux) for a repair. I hope this info was helpful, if so, please leave feedback, it helps my rating, Thanks, Rene(The Vacuum Doctor)

Try dialing the control valve to the mid way position. If the unit still shuts down with the bag full light on you have a damaged control valve under the dial on the top of the vac.
This valve failure is common in this model and can only be repaired by someone with original AERUS Electrolux repair parts, generally at an AERUS repair shop.

This vac is prone to a control valve failure with the exact symptoms you describe. There is a dial valve on top of the machine designed to regulate how full the bag will get. The valve which sits underneath the dial on the vac likely has a broken plunger and will need to be replaced. Take it to an AERUS Electrolux dealer / shop for an experienced tech to work on.

The control valve has gone bad. This is the dial that you move on the top of the vacuum that has little indents on it.
You cannot do anything to bypass this problem from outside the machine.
This is not a repair that you can make yourself. You should look in your local yellow pages for Aerus (new name for electrolux) under vacuum cleaners, or go to www.aerusonline.com and find your local dealer. It is not too expensive to have fixed, it is a common issue with later model electroux vacuums.

You can try a test to see if it the valve. Remove the bag from the vacuum, look at the back of the bag holder near the motor, in the upper right or left depending on your model. You will see a very small hole 1/16 or an inch or so. Put a piece of tape of some sort to close off the hole. Replace the bag, turn on the vacuum, if it is a bad valve, the tape will override the bag full action, and the vacuum will run.

It is not advisable to run the vacuum this way since it will overheat, damage the thermostat, and can destroy the motor. A motor will cost over $200.00, the valve can be replaced for a lot less….

it probably does think you have a full bag.make sure you have it cleaned out and has a bag in there or it might be the sensor for the vacuum and is not working properly. contact your nearest electrolux vac store.or you are not using proper bags.

The problem was a sticking switch that was not being reset. The vacuum on/off switch mechanism is comprised of two switches. One is the main switch that turns the vacuum on and off. The second is a shut off switch that gets tripped when the full bag sensor is engaged. This second switch is supposed to get reset when you push the on/off switch on the outside of the machine. The full bag shutoff switch was stiff and it, therefore, was taking a couple of presses of the on/off switch to move the shutoff switch back into the running position.

Either there is something wrong with your switch. Which it doesnt sound like it. Take it to your dealer or call another one it sounds like the control valve needs to be replaced. I am a dealer 1-866-966-9350.

There is no reset button on the 2100. If it shuts down, the indicator lights will tell you why. If it has been overheated, there is a self-resetting switch which will shut the motor down and the light will come on to indicate that particular problem. When you turn the machine off and then back on, it should re-start provided you have given the motor ample time to cool down. This will not solve the problem as to why it overheated in the first place. There are also lights and auto-switches that will control full bag and no bag. The machine will not run with no bag and a full bag will cause it to run for a few seconds and shut off.