I had a similar problem in my second hand Tata Indigo LX...
I had to replace all the regulators of the power windows.
Fortunately i was at the garage while the power windows were rectified. The garage charged me 1200.00 for the labor and cost of the regulator. The next time when this happened to other window i changed it myself by (DIY)
If you go to ASS
they will not try to check the individual parts, but will insist in replacing the entire set of the motor and regulator change. The ASS
quoted me 3K - 4K.
The DYI costed me only 500.00 for the new regulator per window. So saved 700.00 which i had to give to the garage. And since i also had time i also cleaned all the debris n dirt inside the door panel.
I forgot to take pictures of my DIY but i am posting a link which explains the detail of each step to be followed for this DIY
In a power window there are 2 major elements.
1) Motor - Which rotates the gear clockwise or anticlockwise for the window to roll up or down
2) Regulator - Which actually is a mechanism (which varies for different cars) which converts the rotary motion of the motor into upward and downward movement.
The window glass end is fixed to this regulator end which when the motor rotates, moves the windows up and down.
Check out this web page. It gives a detail DIY on to check and repair the power windows. Diagnosing and replacing a power window regulator & motor in a Pontiac Grand Am