Blender will not turn on
The Ninja shows no sign of power, pulse technology not working.
Faulty power cord
Check to make sure the power cord is plugged into a working outlet. If so, yet no power is being emitted, consider purchasing a new power cord. Replace using this guide.
Lid not secured
Be sure the lid is securely fastened on the blender. For the blender to work, the lid must lock into place with a 1/8 turn to lock into place located at the top of the handle.
The Ninja is working, food/liquid is leaking from the cup.
Lid not secured
Check to make sure the lid is securely fastened on the Ninja. The pulse technology should not work without this, however the possibility exists.
Improper blade installation
Check to make sure the blades are correctly installed. This is an easy fix, refer to this guide.
Blender cup damage
Check the blender cup/bowl for any cracking or damage. If any damage exists, you will need to purchase a replacement. Try this website.
Blades will not rotate
The Ninja is plugged in, no response when engaging pulse technology.
Power cord failure
Check to make sure the power cord is plugged into a working outlet. If this is not the case, your power cord may be frayed or damaged. Refer to this guide.
Blades are jammed
Check to make sure no chunks of food are jamming the blades. If this is not the problem, try removing the blades, cleaning the Ninja, and replacing the blade.
Blades do not cut/blend efficiently
Pulse technology working, blades not working correctly.
Excessive food/blades jammed
Ensure that a reasonable amount of food is in the Ninja. Too much may cause the blades to not work efficiently. If this is not the case, check to make sure no food is jamming the blades. Try removing all ingredients and cleaning the area as a last resort.
The Ninja stops working during use, blades stop turning.
Power cord unplugged
Check to make sure the the power cord is still plugged into a working outlet. If so, try resetting the outlet and trying again.
Check to make sure the blades are in working condition and not jammed by any chunks of food. If so, remove any blockages and try again.
Motor burned out
As a last resort, check to make sure the the motor is in good working condition. Refer to this guide to examine the motor. As motors are not replaceable except by taking apart an existing Ninja, this is usually a sign to replace the entire device. This problem is extremely rare, so you won't usually experience it.