Transmission Range Switch

The Transmission Range (TR) switch is part of the Park/Neutral position and back-up light switch assembly and is mounted on the transmission manual shaft. The TR switch is a multi-signal switch. The Powertrain Control Module (PCM) supplies ignition voltage to the TR switch on four signal circuits, "A", "B", "C", and "D". Each gear selector lever position grounds one or more of the signal circuits in a unique pattern. To determine the gear range selected by the driver, the PCM compares the voltage combination on the signal circuits to a TR switch combination table stored in memory.