You can get a user manual at the following website.
Locate your oven model number. It is located on a label either on the face of the oven when you open the door or on the side of the door. Put he model number into the website and you will get diagrams, component part numbers and manuals.
I suspect the user manual is not going to help you. Tell me the model number and what is going on.
Manufacturers offer the self cleaning feature on ovens because customers like this feature and the ovens sell. Yet, the manufacturers engineers have not been able to provide a design that will protect all of the components from self cleaning temperature of 900-1,000 degree F.
When you go into the self cleaning model, the door will lock when you reach 500-550 Degree F. The oven temperature will raise to 900-1,000 degrees F. The oven door will not open until the oven temperature drops to 500 degree F after the self cleaning cycle is completed.
Now, You have a high temperature limit switch in your oven. If this switch fails, you will loose power to your control board and you will not be able to open the oven door.
If you have never used your self cleaning feature, the high temperature limit switch may have failed.
Do to the problems involved with the self cleaning feature, knocking out the control board from heat, additional heating element failure, and other components; It is in my professional recommendation as well as my fellow technicians not to use the self cleaning feature. If you do, do not run it for more than 1 hour instead for the manual 4 hours.