How to fix common issues with cheap Harbor Freight Multimeters.



Fixing Harbor Freight Multimeters

Here in the US, Harbor Freight actually gives away multimeters for free when you purchase something else in their store. These aren't very good multimeters but they do the job for non-critical measurements. As an Electronics junkie, I can hardly resist free multimeters so I've 'collected' quite a few over the last couple years. I've found some of them come with some annoying defects out of the box. In this video (article) I'll show you two common defects and how you can fix them.

Harbor Freight Meter

Fixing a hard power switch

In some units, the power switch is very hard to move and is almost 'stuck'. 


Problematic Switch

To fix this, start by opening the multimeter and finding the plastic part that contains the switch and the copper contact. Beware that I've found different models have slightly different shapes but the fix is similar; simply file away some of the plastic material as shown (be careful not to remove it completely). Put the pieces back together and it should be much easier to slide the power switch. 


Removing the PCB (remove screws before this)


The Plastic Switch Piece (yellow)


Filing the Plastic


Fixing LCD display issues

In some other units, I've seen that some of the LCD segments don't turn on as expected. This is caused often by either a dirty contact between the LCD and the PCB or simply by bad positioning that might occur because of mechanical shock while in transport. In this case, you will have to remove also the pcb by removing the screws attaching it to the case.

Segment Missing


Use a contact cleaner spray to remove dirt from the contacts. If you don't have a spray, then alcohol should do the trick as well.

Assemble the unit back together and enjoy your free multimeter.

Exposing the LCD Contacts


Using Contact Cleaner



Comments, questions, suggestions? You can reach me at: contact (at sign) paulorenato (dot) com