2006 Mazda MX-5 Miata BaseFACTORY OEM SERVICE PROCEDURE

DTC P0850: Notes

DETECTION CONDITION AND POSSIBLE CAUSE (DTC P0850)

DTC P0850 Neutral switch input circuit problem
DETECTION CONDITION 
  • The PCM monitors changes in input voltage from the neutral switch. If the PCM does not detect the voltage changes while driving the vehicle at a vehicle speed above 30 km/h {19 mph}  and clutch pedal turns press and depress 10 times  repeatedly, the PCM determines that the neutral switch circuit has a malfunction
Diagnostic support note 
  • This is a continuous monitor (CCM).
  • The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
  • PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
  • FREEZE FRAME DATA is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • Neutral switch malfunction
  • Poor connection of neutral switch connector or PCM connector
  • Short to ground in wiring harness between neutral switch terminal 2A and PCM terminal 1X
  • Open circuit in wiring harness between neutral switch terminal 2A and PCM terminal 1X
  • Open circuit in wiring harness between ground and neutral switch terminal 1A
  • PCM malfunction
G04317734Courtesy of MAZDA MOTORS CORP.
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