Park / Neutral Position Switch Circuit
CIRCUIT DESCRIPTIONThe park/neutral position switch goes on when the shift lever is in the N or P shift position. When it goes on the terminal NSW of the ECM is grounded to body ground via the starter relay and theft deterrent ECU, thus the terminal NSW voltage becomes 0 V. When the shift lever is in the D, 2, L or H position, the park/neutral position switch goes off, so the voltage of ECM terminal NSW becomes battery positive voltage, the voltage of the ECM internal power source.
If the shift lever is moved from the N position to the D position, this signal is used for air-fuel ratio correction and for idle speed control (estimated control), etc.
When the park/neutral position switch is off, code "51" is output in the test mode diagnosis. (This is not abnormal.)
DIAGNOSTIC CHART
HINT: This diagnosis chart is based on premise that the engine is cranked normally. If the engine is not cranked, proceed to the matrix chart of problem symptoms.
WIRING DIAGRAM
INSPECTION PROCEDURE