Easy
15-30 minutes
It is a genuine manufacturer-approved replacement switch, it is specially made for a Makita drill. This is the part of the tool handling on/off and variable speed functions. Due to regular use or other factors mechanical or electrical components may begin to fail eventually requiring a replacement switch. It has a durable plastic body and it is sold individually.
Switch Unit 638143-4
OEM part for: Makita
Part Number: 638143-4
$39.83
In Stock
Ships within 1 business day 
Compatibility
This Switch Unit will fit the following 4 machines. Confirm this part works with your model, and view the detailed model diagrams and repair help we have to offer.
Makita
This item works with the following types of products:
- Drill Parts
This part replaces obsolete part #: 650528-4
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Customer Repair Instructions ?
All our customer repair instructions are solicited directly from other customers just like you who have purchased and replaced this exact part.
Switch would only operate drill in reverse direction.
Patrick - April 10, 2016
👍 1 of 1 people found this instruction helpful
Tool Type
Cordless Drill
Difficulty
Easy
Time
Less than 15 minutes
Tools Used
Screwdriver
Parts Used
Very simple fix. Remove about 10 screws. Apply slight pressure to separate housing. Remove and replace switch. Reassemble housing and install screws.
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The speed control trigger switch on my cordless drill only worked intermittently. And when it did work, the drill would only run full speed. I suspected the trigger switch but did not rule out the mo
Vincent - March 9, 2019
Tool Type
Cordless Drill
Difficulty
Easy
Time
30-60 minutes
Tools Used
Screwdriver
Parts Used
The two halves of the drill body were held together with approx. eight identical screws. Removing the screws allowed the halves to come apart revealing the interior parts. Following the wiring colors, I disconnected wires from the switch and reconnected them in the same place in the new switch. The new switch fit into place perfectly. I then replaced the brushes by removing the old and putting in the new. Getting the two halves back together proved a bit tricky but with patience and a couple tries it all went back together OK. Replace screws and done! Drill works like new and I saved $150 dollars.
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Low end of variable speed not responding
Robert - February 4, 2017
Tool Type
Cordless Drill
Difficulty
Easy
Time
15-30 minutes
Tools Used
Screwdriver, Pliers, Power Drill, long nose pliers
Parts Used
Remove screws holding cover over switch
Remove cover
Look at how wires are dressed.
Lift switch and uninstall wire connectors
Replace wires you removed.
Insert switch being careful to redress wires back to their original position.
Make sure you insert the two prongs that connect to the battery.
Put your thumb on the switch to hold it in position while you reinstall cover.
Press cover into position.
Reinstall all screws.
Test drill.
Remove cover
Look at how wires are dressed.
Lift switch and uninstall wire connectors
Replace wires you removed.
Insert switch being careful to redress wires back to their original position.
Make sure you insert the two prongs that connect to the battery.
Put your thumb on the switch to hold it in position while you reinstall cover.
Press cover into position.
Reinstall all screws.
Test drill.
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broken spring terminal
RICHARD - November 16, 2015
Tool Type
Cordless Drill
Difficulty
Easy
Time
Less than 15 minutes
Tools Used
Screwdriver
Parts Used
Unscrew housing, disconnect switch unit and replace with new unit.
Match-up wires (red+,black-) per connections on existing switch.
Match-up wires (red+,black-) per connections on existing switch.
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Our customer service team are at the ready daily to answer your part and product questions. We have a dedicated staff with decades of collective experience in helping customers just like you purchase parts to repair their products.
All our part reviews are solicited directly from other customers who have purchased this exact part. While we moderate these reviews for profanity, offensive language or personally identifiable information, these reviews are posted exactly as submitted and no alterations are made by our team.
All our customer repair instructions are solicited directly from other customers just like you who have purchased and replaced this exact part. While we moderate these reviews for profanity, offensive language or personally identifiable information, these reviews are posted exactly as submitted and no alterations are made by our team.
Based on data from past customer purchasing behaviors, these parts are most commonly purchased together along with the part you are viewing. These parts may be necessary or helpful to replace to complete your current repair.
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