Coolant Temperature Switch
WARNING: This page is about a different car, the 2001 Suzuki Swift and 2000 Suzuki Swift. However, it is still accessible from the selected car via links, so may be relevant.
Heat temperature switch and measure continuity between switch terminal and switch body. At temperature of 233°F (112°C) or greater, continuity should not exist. At temperature of 223°F (106°C) or less, continuity should exist. Replace coolant temperature switch if continuity is not as specified.