Here it is, as shown in the picture below, behind the glove box and towards the kick panel.
Blower motor is generally held by three 10mm screws, when you remove the connector and screws, pull it out downwards carefully.
Check the impeller rotation with hand, it should rotate freely without any restrictions without any bearing noise. Provide 12V from any source which can supply atleast 5A, such as the car battery, to the motor and check its speed. Extreme care must be taken not to touch the moving parts and hold the blower firmly. If it passes this test then next step is to check voltage on the original connector for the blower motor. Switch the engine on, slide the fan speed control to maximum and check the voltage on the connector it should read 13+ VDC on voltmeter.
If this tests is also passed, then either there is a week ground or your car AC evaporator is badly choked with dust and debris.
Notwithstanding the above, I can assure the technician who replaced the carbon brushes has done something out of specs, that can be either wrong brushes or brushes not seated properly or he must have fiddle around with the wiring. But it is suggested that you must perform the above tests to reach at the root cause of the proble.
