Transmission Range Switch

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The Transmission Range (TR) switch is part of the Park/Neutral Position (PNP) and backup light switch assembly, which is externally mounted on the transmission manual shaft. The TR switch contains 4 internal switches that indicate the transmission gear range selector lever position. The PCM supplies ignition voltage to each switch circuit. As the gear range selector lever is moved, the state of each switch may change, causing the circuit to open or close. An open circuit or switch indicates a high voltage signal. A closed circuit or switch indicates a low voltage signal. The PCM detects the selected gear range by deciphering the combination of the voltage signals. PCM compares actual voltage combination of the switch signals to a TR switch combination chart stored in memory.