Milwaukee M18 F1WF12 & M18 FID LED repair

This article explains repair of the Milwaukee M18 F1WF12 & M18 FID impact tools where one or more of the ‘power' LEDs has failed.

Above, the subject tools.

In my case, both of the quite similar tools suffered the same failure, total failure of the LED lit up in the above pics (of the repaired tools). In fact both tools suffered failure of the same LED which might hint something else cause premature failure… but the repaired units have not shown further failure.

The original LEDs are white 1206 parts with an integral lens. They turned out to be quite difficult to source, so ordinary flat 1206 cool white LEDs were used.

Above, the footprint of the replacement LEDs. These were purchased for $2/100 including shipping on Aliexpress.

The replacement LED under test, 3.2V @ 20mA  is pretty standard for a white LED.


Only proceed if you are competent to do surface mount PCB rework and have the necessary tools.

  1. Remove the battery if fitted.
  2. Remove all of the screws holding the case halves together, note that two are longer.
  3. Carefully lift the top half off leaving the rest in place in the lower half.
  4. Slide the LED/switch assembly out of the recess in the lower half, and carefully unclip the black plastic escutcheon to give access to the PCB.
  5. Remove the faulty LED (remember that the priority is to preserve the PCB), clean the PCB, apply some flux and solder the replacement onto the board (anode nearest the PCB edge). Clean up.
  6. Test.
  7. Reverse the disassembly procedure.


The problems experienced speaks to the quality of Milwaukee tools.

It seems unlikely that two LEDs in the same position fail, but that might be that they are the most used positions and therefore with sufficient time, more LEDs will fail.

If (/when) another LED fails, it it is one not replaced, then all LEDs will be replaced in both tools.