A food blender is a far less complex machine than most people imagine. Because of this simplicity, you can easily determine the cause of a non-working blender. Typically you can narrow the potential problems to three causes: the motor has burned out, the blades are clogged, or electric power to the blender has been interrupted. Once you identify the cause, you should be able to remedy the problem with little trouble. To fix a non-functioning blender, follow the five steps below.
Step 1 - Test for Power Connectivity
First, test the blender's electrical switch by disconnecting the power cord from the wall receptacle and turning the blender switch to its "on" position. With your voltmeter set on the RX1 scale, clip the meter's probes to the two metal prongs that are normally plugged into a power receptacle. While watching the meter's readings, press the blender's switches, one at a time.
If you see a low reading on the meter while the switches are in the "on" position, your switch is working properly. Otherwise, you will see an infinity reading on the meter, indicating that the blender's switch is defective.
Step 2 - Clean the Electrical Terminals
To expose the screws that hold the switch housing cover in place, first remove the plastic faceplate that covers the housing and switch buttons. Then remove the screws that attach the plate to the housing.
With the contacts and switches now exposed, use a contact spray solvent to clean the contacts, openings, and terminals at the rear of the switch block.
Finally, connect the power cord to a wall receptacle and try the switches. If the blender still fails to work, go on to the next step.
Step 3 - Test the Fuse
Locate the fuse. It should be at the end of a wire lead coming from a terminal where the power cord is connected. With your voltmeter still set to RX1, clip its probe ends to the two lead wires or terminals.
If the meter reading is high, you will need to replace the fuse. If you need to replace the fuse, you'll find its size engraved on the metal cap of the fuse. Many fuses look alike, so be sure you get the right size.
Step 4 - Check the Blender for Jamming
Disassemble the drive as much as possible and try turning the blade shaft. If it's jammed, check to see what is jamming it. Most likely you will discover debris in the blender blades. If necessary, replace the coupling.
Step 5 - Perform the Final Check
If you can get the blade shaft turning properly, with all debris removed that might cause jamming, give the blender another test. Plug it in and press the blender's switches. Unless the motor is burned out, the blender should now work properly. Replace all screws and plates.