Knock Sensor
WARNING: This page is about a different car, the 2002 Suzuki XL-7, 2002 Suzuki Vitara, 2002 Suzuki Grand Vitara, 2002 Suzuki Esteem, and 2002 Suzuki Aerio. However, it is still accessible from the selected car via links, so may be relevant.
For testing procedures, see DTCs P0327 and P0328 in appropriate SELF-DIAGNOSTICS article.