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Home >> Mazda >> 1994 >> Navajo 2WD V6-4.0L OHV >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Transmission Position Sensor/Switch >> Description and Operation >> Component (M/T)
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Component (M/T)

PURPOSE
The Powertrain Control Module (PCM) uses the Park/Neutral Position Switch (input) to determine engine load and adjust engine operating parameters according to PCM programming.

OPERATION
The PCM sends a 5 Volt reference voltage through pin No.30 which travels to a terminal on the Park/Neutral Position Switch. The other terminal of the Park/Neutral Position Switch connects to a common ground circuit that returns to to PCM pin No.46. With the transmission in the neutral position the Park/Neutral Position Switch closes and allows current flow from PCM pin No.30 through the switch contacts and out to PCM pin No.46.
This current flow results in a measurable voltage drop at PCM pin No.30 from 5 Volts to approximately 1 Volt or less.

The Park/Neutral Position Switch opens the circuit when the transmission is in any gear position other than neutral. The interuption of current flow causes the voltage at PCM pin No.30 to return to 5 Volts.
The PCM monitors the voltage changes at pin No.30 and uses that information to determine transmission gear position.

NOTE: On manual transmission applications the Park/Neutral Position Switch and the Clutch Pedal Position Switch share the same (input) circuit and terminal pin No.30 to the Powertrain Control Module.

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