WARNING: This page is about a different car, the 2008 Suzuki Grand Vitara, 2007 Suzuki Grand Vitara, and 2006 Suzuki Grand Vitara. However, it is still accessible from the selected car via links, so may be relevant.
Check brushes for wear.
Measure length of brushes and if below limit, replace brush.
Brush length
Standard: 12.3 mm (0.48 in.)
Limit: 5.5 mm (0.22 in.)
Fig 1: Measuring Length Of Brush
Courtesy of SUZUKI OF AMERICA CORP.
Install brushes to each brush holder and check for smooth movement.