Oscillating Tool: Won't Turn on
If your oscillating tool isn't turning on, not to worry, we can help you diagnose the problem. First, look for signs of wear in tear on the following parts: the circuit board, carbon brush, switch, cord, armature, and field. Once you have determined which part is damaged, read on for tips on how you can repair this yourself - it might be easier then you think. Reference your owner's manual for detailed instruction for your model.
You can test the armature to check its condition. There are three test to use when checking an armature. The first is continuity test. With the armature removed from the unit, stand it up on a bench. Attach one end...
You can test the armature to check its condition. There are three test to use when checking an armature. The first is continuity test. With the armature removed from the unit, stand it up on a bench. Attach one end of the ohmmeter to the shaft, for ground, and the other to the bar on the commutator. Move the probe to each bar on the commutator, checking all of the bars. If the ohmmeter shows a reading on one of the bars, this will indicate a short and a bad armature.
The second test is a bar to bar test, to determine the resistance. Attach one probe to a bar on the commutator and the other probe on the bar right beside it. There will be a specific reading for this, depending on the design of the armature. Most importantly, there is not a large fluctuation here between the values, indicating a fault. If there is an increase in resistance, this will indicate there is a broken or burned out wire in the coil. Should the resistance drop, that means there is a short. Move around the commutator, checking each bar.
The third test is the 180-degree test. Attach the two ends of the ohmmeter on the commutator bars, directly across from each other. There will be a specific set of readings for this, depending on the design of your unit. Once again, what is important is that there is not a large fluctuation in values, which would indicate a fault. If there is an increase in resistance, that would indicate a broken or burnt wire. If it drops, there is a short. Continue this test on all the bars If an armature fails any of these tests, it is recommended that you replace it. Install the armature into the field and position the motor assembly back together in the housing. Reassemble the housing back together and reinstall the brushes with the brush caps.
You can check the condition of the field by performing a couple of tests. Using a multimeter, you can check the field for continuity. Set the multimeter to an ohmmeter and...
You can check the condition of the field by performing a couple of tests. Using a multimeter, you can check the field for continuity. Set the multimeter to an ohmmeter and place a lead on each end of the coil in the field. You will have to perform this test for each coil in the field. If the reading is infinity for one, or more, of the coils, then the field is bad and requires replacement. If there is a major variance between the coils, then the field needs to be replaced. Slide the armature into the field and position the field into the housing. Reattach the wires and reassemble the case back together. Install the brushes and brush caps.
To check the circuit board, remove the brush caps and carbon brushes. Some models do not have caps. Brushes can only be removed once the housing is open. Open the oscillating tool housing and locate the circuit board. Make sure all of the wires are attached to the circuit board before further diagnostics. A broken or loose wire at the circuit board may be the culprit.
Remove the circuit board and examine it for burn marks, melting and broken components. When replacing the circuit board, take a picture or make a diagram of the wire connections, allowing for easier reassembly. Remove the old wires from...
To check the circuit board, remove the brush caps and carbon brushes. Some models do not have caps. Brushes can only be removed once the housing is open. Open the oscillating tool housing and locate the circuit board. Make sure all of the wires are attached to the circuit board before further diagnostics. A broken or loose wire at the circuit board may be the culprit.
Remove the circuit board and examine it for burn marks, melting and broken components. When replacing the circuit board, take a picture or make a diagram of the wire connections, allowing for easier reassembly. Remove the old wires from the circuit board and attach on the new circuit board. Reinstall in the housing and reassemble the housing back together. Reinstall the carbon brushes with the brush caps.