Circuit/System Description
WARNING: This page is about a different car, the 2007 GMC Yukon XL, 2007 GMC Yukon, 2007 Cadillac Escalade EXT, 2007 Cadillac Escalade ESV, and 2007 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.
The clutch pressure control (PC) solenoid 2 flows fluid to the 3-5-R clutch when commanded OFF and exhausts fluid when commanded ON. The clutch PC solenoid 2 regulates the transmission fluid pressure to the 3-5-R clutch. The transmission fluid pressure (TFP) switch 1 opens (high) under fluid pressure and closes (low) when no pressure is present. The transmission control module (TCM) calculates gear ratio based on data from the automatic transmission input speed sensor (ISS) and the output speed sensor (OSS). The TCM compares the known transmission gear ratio to a calculated gear ratio for each commanded gear.