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Diagnostic Procedure

DTC P0850:00 DIAGNOSTIC PROCEDURE

STEP INSPECTION RESULTS ACTION
1 RECORD VEHICLE STATUS AT TIME OF DTC DETECTION TO UTILIZE WITH REPEATABILITY VERIFICATION
NOTE:
  • Recording can be facilitated using the screen capture function of the PC.
  • Record the FREEZE FRAME DATA/snapshot data on the repair order.
 - Go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY
  • Verify related Service Bulletins and/or on-line 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 INSPECT NEUTRAL SWITCH CONNECTOR CONDITION
  • Switch the ignition 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 and/or terminals, then go to Step 9.
No Go to the next step.
4 INSPECT NEUTRAL SWITCH GROUND CIRCUIT FOR OPEN CIRCUIT
  • Verify that the neutral switch connector is disconnected.
  • Inspect for continuity between neutral switch terminal B (wiring harness-side) and body ground.
  • Is there continuity?
 Yes Go to the next step.
No Refer to the wiring diagram and verify whether or not there is a common connector between neutral switch terminal B and body ground. If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Inspect for the following:
    • Open circuit between neutral switch and body ground
      • Loose or lifting ground point
  • Repair or replace the malfunctioning part.

Go to Step 9.
5 INSPECT PCM CONNECTOR CONDITION
  • 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 and/or terminals, then go to Step 9.
No Go to the next step.
6 INSPECT NEUTRAL SWITCH SIGNAL CIRCUIT FOR SHORT TO GROUND
  • Verify that the neutral switch and PCM connectors are disconnected.
  • Inspect for continuity between neutral switch terminal A (wiring harness-side) and body ground.
  • Is there continuity?
 Yes Refer to the wiring diagram and verify whether or not there is a common connector between neutral switch terminal A and PCM terminal 1K.
If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Repair or replace the wiring harness which has a short to ground.

Go to Step 9.
No Go to the next step.
7 INSPECT NEUTRAL SWITCH SIGNAL CIRCUIT FOR OPEN CIRCUIT
  • Verify that the neutral switch and PCM connectors are disconnected.
  • Inspect for continuity between neutral switch terminal A (wiring harness-side) and PCM terminal 1K (wiring harness-side).
  • Is there continuity?
 Yes Go to the next step.
No Refer to the wiring diagram and verify whether or not there is a common connector between neutral switch terminal A and PCM terminal 1K.
If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Repair or replace the wiring harness which has an open circuit.

Go to Step 9.
8 INSPECT NEUTRAL SWITCH Yes Replace the neutral switch, then go to the next step.
(See NEUTRAL SWITCH REMOVAL/INSTALLATION [C66M-R].)
No Go to the next step.
9 VERIFY DTC TROUBLESHOOTING COMPLETED
  • Always reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS. (See CLEARING DTC .)
    CAUTION:
    • While performing this step, always operate the vehicle in a safe and lawful manner.
  • When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later.
  • 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. (See ON-BOARD DIAGNOSTIC TEST .)
  • Is the PENDING CODE for this DTC present?
 Yes Repeat the inspection from Step 1.
Go to the next step.
No Go to the next step.
10 VERIFY AFTER REPAIR PROCEDURE Yes Go to the applicable DTC inspection.
(See DTC TABLE .)
No DTC troubleshooting completed.


DTC P0850:00 DIAGNOSTIC PROCEDURE

STEP INSPECTION RESULTS ACTION
1 RECORD VEHICLE STATUS AT TIME OF DTC DETECTION TO UTILIZE WITH REPEATABILITY VERIFICATION
NOTE:
  • Recording can be facilitated using the screen capture function of the PC.
  • Record the FREEZE FRAME DATA/snapshot data on the repair order.
 - Go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY
  • Verify related Service Bulletins and/or on-line 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 INSPECT NEUTRAL SWITCH CONNECTOR CONDITION
  • Switch the ignition 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 and/or terminals, then go to Step 9.
No Go to the next step.
4 INSPECT NEUTRAL SWITCH GROUND CIRCUIT FOR OPEN CIRCUIT
  • Verify that the neutral switch connector is disconnected.
  • Inspect for continuity between neutral switch terminal B (wiring harness-side) and body ground.
  • Is there continuity?
 Yes Go to the next step.
No Refer to the wiring diagram and verify whether or not there is a common connector between neutral switch terminal B and body ground. If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Inspect for the following:
    • Open circuit between neutral switch and body ground
      • Loose or lifting ground point
  • Repair or replace the malfunctioning part.

Go to Step 9.
5 INSPECT PCM CONNECTOR CONDITION
  • 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 and/or terminals, then go to Step 9.
No Go to the next step.
6 INSPECT NEUTRAL SWITCH SIGNAL CIRCUIT FOR SHORT TO GROUND
  • Verify that the neutral switch and PCM connectors are disconnected.
  • Inspect for continuity between neutral switch terminal A (wiring harness-side) and body ground.
  • Is there continuity?
 Yes Refer to the wiring diagram and verify whether or not there is a common connector between neutral switch terminal A and PCM terminal 1BF.
If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Repair or replace the wiring harness which has a short to ground.

Go to Step 9.
No Go to the next step.
7 INSPECT NEUTRAL SWITCH SIGNAL CIRCUIT FOR OPEN CIRCUIT
  • Verify that the neutral switch and PCM connectors are disconnected.
  • Inspect for continuity between neutral switch terminal A (wiring harness-side) and PCM terminal 1BF (wiring harness-side).
  • Is there continuity?
 Yes Go to the next step.
No Refer to the wiring diagram and verify whether or not there is a common connector between neutral switch terminal A and PCM terminal 1BF.
If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Repair or replace the wiring harness which has an open circuit.

Go to Step 9.
8 INSPECT NEUTRAL SWITCH Yes Replace the neutral switch, then go to the next step.
(See NEUTRAL SWITCH REMOVAL/INSTALLATION [C66M-R].)
No Go to the next step.
9 VERIFY DTC TROUBLESHOOTING COMPLETED
  • Always reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS. (See CLEARING DTC .)
    CAUTION:
    • While performing this step, always operate the vehicle in a safe and lawful manner.
  • When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later.
  • 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. (See ON-BOARD DIAGNOSTIC TEST .)
  • Is the PENDING CODE for this DTC present?
 Yes Repeat the inspection from Step 1.
Go to the next step.
No Go to the next step.
10 VERIFY AFTER REPAIR PROCEDURE Yes Go to the applicable DTC inspection.
(See DTC TABLE .)
No DTC troubleshooting completed.
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