There are many possible reasons why your Milwaukee Circular Saw will not work when you need it. We’ll discuss six of those possible reasons and the solutions to each of them in this article.
But before you continue reading this article, you may first watch the short video I’ve made about this topic. I’ve uploaded it on my YouTube channel but you can also watch it below.
On my video, I briefly discussed each of the possible causes like the lock-off button accidentally pressed, loose trigger or switch, faulty switch, faulty diode, MOSFET failure, motor failure and the possible solutions to each of them.
6 Reasons Why Milwaukee Circular Saw Not Turning On Not Working
1. Lock-Off Button
If you are unlucky like and your Milwaukee saw suddenly bailed on you while you were working then don’t worry. When this happened to me I started by identifying if the lock-off button was pressed.
It is important that you press the lock-off button before pressing the trigger as if the lock is not turned off the power is not sent to the motor. It works as a safety feature in the Milwaukee circular saw.
2. Loosen Trigger and Switch Connection
If turning off the lock didn’t work for you, maybe trying this technique can help you.
I began by opening the housing and removing half of the cover of the Milwaukee saw, after that I inspected and looked for any loose wires or terminals near the trigger switch.
You can use a screw driver to tighten any visible loosen switch to make sure the connection is perfect and fix your saw.
3. Switch Failure
When nothing worked for me I decided to test the switch, I set my multimeter to continuity mode and tested the lower terminals first.
I got a beep and then I checked the upper part of the switch and there was no deep when the switch was pressed. This meant that there was some problem with the switch and I decided to pop it open to clean the metal contacts inside.
If cleaning the metal contact still doesn’t work try replacing the switch with a new one to fix it.
4. Diode Failure
If you still can’t seem to figure out as to why your Milwaukee saw is still not working try testing the diode present on the switch.
I again used my multimeter to diode mode and started testing it, first I placed the red probe on the non-banded side which is the anode and the black probe on the banded side which is the cathode.
If the diode is good and in the working condition it should beep or you should see a small voltage drop in your multimeter. If it’s not good the multimeter will not beep and the diode’s probably short and needs replacing.
5. MOSFET Failure
There is a high chance that you might have not heard about the word “MOSFET”, it is an electrical component used to control high current or power in circuit and my Milwaukee circular saw itself has two MOSFETs.
A bad MOSFET can mean the saw will not receive power and thus won’t work at all. I started by placing the black probe on the source pin and the red probe of my multimeter on the gate pin with the multimeter being set on diode mode.
If the screen shows OL or no beep, the MOSFET is good but if it beeps the gate is probably short and the part needs to be replaced to fix the problem.
6. Motor Failure
This is the most important test you can do to find out why your Milwaukee circular saw is not working and fix it.
Start by removing all the screws of the outer cover of the saw and remove the plastic cover out of the way to access the motor of the saw. Then using an external battery connect the motor of the saw directly with the battery with the blade removed.
If the motor runs and turns on completely fine the circuit might be at fault but if the motor doesn’t run at all, the motor is at fault and replacing it can fix the issue for you and make your Milwaukee saw work like new again.
