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 DTC P0850 [L3 Turbo]

DTC P0850 [L3 Turbo]

id0102b7810100

DTC P0850

Neutral switch circuit malfunction

DETECTION CONDITION

• PCM monitors changes in the input voltage from the neutral switch. If the PCM does not detect the voltage change while driving the vehicle at a speed above 30 km/h {19 mph} and the clutch pedal is depressed and released 10 times repeatedly, the PCM determines that the neutral switch circuit has a malfunction
Diagnostic support note
• This is a continuous monitor (CCM).
• 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.
• DTCs are stored in PCM memory.

POSSIBLE CAUSE

• Neutral switch malfunction
• Poor connection of the neutral switch connector or PCM connector
• Short to ground between neutral switch terminal B and PCM connector terminal 1W
• Open circuit in the wiring harness between neutral switch terminal B and PCM connector terminal 1W
• Open circuit in the wiring harness between ground and brake switch terminal A.
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS 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 Information availability.
• Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service information.
If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
CLASSIFY HIGH INPUT OR LOW INPUT
• Connect the WDS or equivalent to the DLC-2.
• Access the CPP/PNP PID.
• Verify the CPP/PNP PID when gear is in the neutral position.
• Is the CPP/PNP PID always off?.
Yes
Go to Next step.
No
Go to Step 10.
4
INSPECT NEUTRAL SWITCH CONNECTOR FOR POOR CONNECTION
• Turn the ignition switch to off.
• Disconnect the neutral switch connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 14.
No
Go to the next step.
5
CLASSIFY NEUTRAL SWITCH OR CIRCUIT
• Connect the WDS or equivalent to the DLC-2.
• Access the CPP/PNP PID.
• Connect a jumper wire between neutral switch terminal A and B (harness-side).
• Is the CPP/PNP PID on?
Yes
Go to the next step.
No
Go to Step 7.
6
INSPECT NEUTRAL SWITCH
• Perform the neutral switch inspection.
• Is the neutral switch normal?
Yes
Go to Step 14.
No
Replace the neutral switch, then go to Step 14.
7
INSPECT NEUTRAL SWITCH GROUND CIRCUIT FOR OPEN CIRCUIT
• Inspect for continuity between neutral switch terminal A (harness-side) and body ground.
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the neutral switch power circuit for an open circuit, then go to Step 14.
8
INSPECT PCM CONNECTOR FOR POOR CONNECTION
• Turn the ignition switch to off.
• Disconnect the PCM connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 14.
No
Go to the next step.
9
INSPECT NEUTRAL SWITCH SIGNAL CIRCUIT FOR OPEN CIRCUIT
• Inspect for continuity between neutral switch terminal B (harness-side) and PCM terminal 1W (harness-side).
• Is there continuity?
Yes
Repair or replace wiring harness for an open circuit, then go to Step 14.
No
Go to Step 14.
10
INSPECT NEUTRAL SWITCH CONNECTOR FOR POOR CONNECTION
• Turn the ignition switch to off.
• Disconnect neutral switch connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 14.
No
Go to the next step.
11
CLASSIFY NEUTRAL SWITCH OR CIRCUIT
• Connect the WDS or equivalent to the DLC-2.
• Access the CPP/PNP PID.
• Verify that the CPP/PNP PID changes from on to off when the neutral switch connector is disconnected.
• Does the CPP/PNP PID change from on to off?
Yes
Go to the next step.
No
Go to Step 13.
12
INSPECT NEUTRAL SWITCH
• Perform the neutral switch inspection.
• Is the neutral switch normal?
Yes
Go to Step 14.
No
Replace the neutral switch, then go to Step 14.
13
INSPECT NEUTRAL SWITCH SIGNAL CIRCUIT FOR SHORT TO GROUND
• Inspect for continuity between neutral switch terminal B (harness-side) and body ground.
• Is there continuity?
Yes
Repair or replace the wiring harness for a short to ground, then go to Step 14.
No
Go to the next step.
14
VERIFY TROUBLESHOOTING OF DTC P0850 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Start the engine.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Drive vehicle above 30 km/h {19 mph} and stop vehicle.
• Depress and release clutch pedal more than 10 times during the drive cycle.
• Is the PENDING CODE for this DTC present?
Yes
Replace PCM, then go to the next step.
No
Go to the next step.
15
VERIFY AFTER REPAIR PROCEDURE
• Perform the "After Repair Procedure".
• Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
Troubleshooting completed.