DTC P0704: Clutch Pedal Switch: Description
WARNING: This page is about a different car, the 2002 GMC Sierra, 2002 GMC Cab & Chassis Sierra, 2002 Chevrolet Silverado, and 2002 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Battery voltage is supplied from the brake fuse to the clutch switch. The clutch switch is a normally-closed switch. When the clutch pedal is released, the clutch pedal position switch signal circuit is pulled up to battery voltage. When the clutch pedal is applied, the switch opens, and the voltage drops to 0 volts. If the Engine Control Module (ECM) detects a specified number of vehicle speed transitions without detecting a clutch switch transition, DTC P0704 will set.