Remington MB4040 Troubleshooting
Cordless 120V mustache and beard trimmer released by Remington Products. Item # MB4040.
Remington MB4040 won’t turn on
Plug in the charger. An LED light below the power button on the Remington MB4040 will illuminate if it’s receiving a charge. Allow it to charge for a few minutes if it fails to receive any charge the battery is most likely dead. If the battery is completely dead it will need to be replaced.
Power supply button malfunction
Cycle power by turning the device on and off listening for audible signs of the motor attempting to start. If no audible signs are heard, disassemble and inspect the internal workings of the power supply.
Remington MB4040 won’t hold a charge
Unplug and clean the charger then plug it back in. If that does not fix the discrepancy the charger may be broke and needs to be replaced. Try using a similar charger with the same specs and see if you get a charge that way.
Do not exceed 5 volts if using another small electronics charger.
Try using a different outlet. If you really want to tinker use a multimeter to check the outlet voltage.
If the battery is completely dead it will need to be replace. Remove and replace the battery. Step by step battery replacement is shown in this link.
Device spontaneously shuts off
Defective thermal switch
If the trimmer intermittently stops working with the power switch still in the 'on' position it is possible the device has overheated and the thermal switch has activated and shut off the device to protect it from any damage. If the trimmer feels very warm to the touch, give it 10 minutes or more to cool down before continuing use. If it does not feel warm and the problem persists the thermal switch may be defective. Replacement of this switch can be found using these steps.
Zoom wheel will not adjust
The zoom wheel is used to adjust the height of the blades.
Gear is disengaged
Make sure all the internal hardware is properly engaged and look for any signs of binding.
If binding is found, the device must be taken apart to remove binding from wheel. Use this guide to access and disassemble the zoom wheel.
Fails to remove Hair
If the shaving experience is rough, or the blade fails to remove some hair.
Remove and replace the blade using this guide.
Remington MB4040 binds or has a low motor RPM
Debris is caught in the motor
Disassemble the Remington MB4040 and clean any dirt and debris that have accumulated over time. Reassemble and perform a function check.
If the Remington MB4040 is fully charged and it continually sounds like it is low on battery the motor may be faulty. Remove and replace the motor by using the guide with the attached link.