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 DTC P0850 [MZR-CD (RF Turbo)]

DTC P0850 [MZR-CD (RF Turbo)]

id0102f1810100

DTC P0850

Neutral switch circuit malfunction

DETECTION CONDITION

• The PCM monitors the input signal from the neutral switch when shifting. If the neutral switch signal is not input even once even when vehicle speed is more than 10 km/h {6.2 mph} the shift lever is operated more than five times, the PCM determines that there is a malfunction in the neutral switch circuit.
Diagnostic support note
• 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.
• FREEZE FRAME DATA is available.
• The DTC is stored in the PCM memory.

POSSIBLE CAUSE

• Neutral switch malfunction
• Connector or terminal malfunction
• Short to ground in wiring harness between neutral switch terminal A and PCM terminal 110
• Open circuit in wiring harness between neutral switch terminal B and ground
• Open circuit in wiring harness between neutral switch terminal A and PCM terminal 110
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
• Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Verify related service repair information availability.
• Is any related repair information available?
Yes
Perform repair or diagnosis according to the available repair information.
• If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
VERIFY CURRENT SIGNAL STATUS: IS CONCERN INTERMITTENT OR CONSTANT?
• Connect the WDS or equivalent to the DLC-2.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Start the engine.
• Is the PENDING CODE for this DTC present?
Yes
Go to the next step.
No
Intermittent concern exists.
Perform the "INTERMITTENT CONCERN TROUBLESHOOTING".
4
INSPECT NEUTRAL SWITCH CONNECTOR FOR POOR CONNECTION
• Turn the engine switch off.
• Inspect for poor connection (such as damaged/pulled-out terminals, corrosion).
• Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 10.
No
Go to the next step.
5
INSPECT NEUTRAL SWITCH SIGNAL CIRCUIT FOR SHORT TO GROUND
• Turn the engine switch off.
• Inspect for continuity between neutral switch terminal A and body ground.
• Is there continuity?
Yes
Repair or replace the wiring harness for a short to ground, then go to Step 10.
No
Go to the next step.
6
INSPECT NEUTRAL SWITCH GROUND CIRCUIT FOR OPEN CIRCUIT
• Turn the engine switch off.
• Inspect for continuity between neutral switch terminal B and body ground.
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for an open circuit, then go to Step 10.
7
INSPECT NEUTRAL SWITCH
• Inspect the neutral switch.
• Is there any malfunction?
Yes
Replace the neutral switch, then go to Step 10.
No
Go to the next step.
8
INSPECT PCM CONNECTO FOR POOR CONNECTION
• Turn the engine switch off.
• Inspect for poor connection (such as damaged/pulled-out terminals, corrosion).
• Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 10.
No
Go to the next step.
9
INSPECT NEUTRAL SWITCH SIGNAL CIRCUIT FOR OPEN CIRCUIT
• Turn the engine switch off.
• Inspect for continuity between neutral switch terminal A and PCM terminal 110.
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for an open circuit, then go to the next step.
10
VERIFY TROUBLESHOOTING OF DTC P0850 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Start the engine.
• Is the PENDING CODE for this DTC present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
11
VERIFY AFTER REPAIR PROCEDURE
• Perform the Repair Verification Drive Mode.
• Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
Troubleshooting completed.