DTC P0850 [L8, LF]

id0102b1810100

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 (Mode 2/Mode 12) is available.
•  The DTC is stored in the PCM memory.
POSSIBLE CAUSE
•  Neutral switch connector or terminals malfunction
•  Neutral switch malfunction
•  Short to ground in wiring harness between neutral switch terminal 2A and PCM terminal 1X
•  PCM connector or terminals malfunction
•  Open circuit in wiring harness between neutral switch terminal 1A and body ground
•  Open circuit in wiring harness between neutral switch terminal 2A and PCM terminal 1X
•  PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION
1
VERIFY FREEZE FRAME DATA (MODE 12) HAS BEEN RECORDED
•  Has the FREEZE FRAME DATA (Mode 12) been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA (Mode 12) on the repair order, then go to the next step.
2
VERIFY RELATED SERVICE 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
VERIFY WHETHER MALFUNCTION IS OPEN CIRCUIT OR SHORT TO GROUND
•  Connect the M-MDS to the DLC-2.
•  Perform the PID/DATA Monitor and Record Procedure and access the CPP/PNP PID.
•  Verify the CPP/PNP PID during operating the gear.
•  Is the PID normal?
Yes
Go to Step 13.
No
If the CPP/PNP PID is always Drive:
•  Go to the next step.
If the CPP/PNP PID is always Neural:
•  Go to Step 8.
4
INSPECT NEUTRAL SWITCH CONNECTOR AND TERMINALS
•  Turn the ignition switch 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 connector or terminals, then go to Step 13.
No
Go to the next step.
5
INSPECT NEUTRAL SWITCH
•  Inspect the neutral switch.
•  Is there any malfunction?
Yes
Replace the neutral switch, then go to Step 13.
(See NEUTRAL SWITCH REMOVAL/INSTALLATION [M15M-D].)
(See NEUTRAL SWITCH REMOVAL/INSTALLATION [P66M-D].)
No
Go to the next step.
6
INSPECT NEUTRAL SWITCH SIGNAL CIRCUIT FOR SHORT TO GROUND
•  Neutral switch connector is disconnected.
•  Inspect for continuity between neutral switch terminal 2A (wiring harness-side) and body ground.
•  Is there continuity?
Yes
If the short to ground circuit could be detected:
•  Repair or replace the wiring harness for a possible short to ground.
If the short to ground circuit could not be detected:
•  Replace the PCM (short to ground in PCM internal circuit).
Go to Step 13.
No
Go to the next step.
7
INSPECT PCM CONNECTOR AND TERMINALS
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector or terminals, then go to Step 13.
No
Go to Step 13.
8
INSPECT NEUTRAL SWITCH CONNECTOR AND TERMINALS
•  Turn the ignition switch 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 connector or terminals, then go to Step 13.
No
Go to the next step.
9
INSPECT NEUTRAL SWITCH GROUND CIRCUIT FOR OPEN CIRCUIT
•  Neutral switch connector is disconnected.
•  Inspect for continuity between neutral switch terminal 1A (wiring harness-side) and body ground.
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for a possible open circuit, then go to Step 13.
10
INSPECT NEUTRAL SWITCH
•  Inspect the neutral switch.
•  Is there any malfunction?
Yes
Replace the neutral switch, then go to Step 13.
(See NEUTRAL SWITCH REMOVAL/INSTALLATION [M15M-D].)
(See NEUTRAL SWITCH REMOVAL/INSTALLATION [P66M-D].)
No
Go to the next step.
11
INSPECT PCM CONNECTOR AND TERMINALS
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector or terminals, then go to Step 13.
No
Go to the next step.
12
INSPECT NEUTRAL SWITCH SIGNAL CIRCUIT FOR OPEN CIRCUIT
•  Neutral switch and PCM connectors are disconnected.
•  Inspect for continuity between neutral switch terminal 2A (wiring harness-side) and PCM terminal 1X (wiring harness-side).
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for a possible open circuit, then go to the next step.
13
VERIFY DTC TROUBLESHOOTING COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Start the engine and warm it up completely.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Drive the vehicle above 30 km/h {19 mph} and stop the vehicle.
•  Depress and release the clutch pedal more than 10 times during drive cycle.
•  Perform the Pending Trouble Code Access Procedure.
•  Is the PENDING CODE for this DTC present?
Yes
Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION [L8, LF].)
No
Go to the next step.
14
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Are any DTCs present?
Yes
Go to the applicable DTC troubleshooting.
(See DTC TABLE [L8, LF].)
No
DTC troubleshooting completed.