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 (Mode 2/Mode 12) is available. The DTC is stored in the PCM memory.
POSSIBLE CAUSE	Neutral switch connector or terminals malfunction PCM connector or terminals malfunction Neutral switch malfunction Open circuit in wiring harness between neutral switch terminal 2A and PCM terminal 1X Open circuit in wiring harness between neutral switch terminal 1A and body ground Short to ground 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.
1		No	Record the FREEZE FRAME DATA (Mode 12) on the repair order, then go to the next step.
2	VERIFY RELATED SERVICE BULLETINS AVAILABILITY Verify related Service Bulletins availability. Is any related Service Bulletins available?	Yes	Perform the repair or diagnosis according to the available Service Bulletins. If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	CLASSIFY HIGH INPUT OR LOW INPUT Connect the M-MDS to the DLC-2. Access the CPP/PNP PID. Verify the CPP/PNP PID when gear is neutral position. Is the CPP/PNP PID always Drive?	Yes	Go to the next step.
3		No	Go to Step 9.
4	INSPECT NEUTRAL SWITCH CONNECTOR AND TERMINALS Turn the ignition switch 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 connector or terminals, then go to Step 14.
4		No	Go to the next step.
5	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 14.
5		No	Go to the next step.
6	CLASSIFY NEUTRAL SWITCH OR CIRCUIT Reconnect the neutral switch and PCM connectors. Connect the M-MDS to the DLC-2. Access the CPP/PNP PID. Connect a jumper wire between neutral switch terminal 2A and 1A. Verify the CPP/PNP PID when gear is neutral position. Is the CPP/PNP PID Neutral?	Yes	Go to the next step.
6		No	Go to Step 8.
7	INSPECT NEUTRAL SWITCH Disconnect the neutral switch connector. Inspect the neutral switch. (See NEUTRAL SWITCH INSPECTION ). Is there any malfunction?	Yes	Replacge the neutral switch, then go to Step 14. (See NEUTRAL SWITCH REMOVAL/INSTALLATION ). (See NEUTRAL SWITCH REMOVAL/INSTALLATION ).
7		No	Go to Step 14.
8	INSPECT NEUTRAL SWITCH CIRCUITS FOR OPEN CIRCUIT Disconnect the neutral switch and PCM connectors. Inspect for continuity between the following terminals: Neutral switch terminal 2A (wiring harness-side) and PCM terminal 1X (wiring harness-side) Neutral switch terminal 1A (wiring harness-side) and body ground Is there continuity?	Yes	Go to Step 14.
8		No	Repair or replace the wiring harness for a possible open circuit, then go to Step 14.
9	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 14.
9		No	Go to the next step.
10	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 14.
10		No	Go to the next step.
11	CLASSIFY NEUTRAL SWITCH OR CIRCUIT Reconnect the neutral switch and PCM connectors. Connect the M-MDS to the DLC-2. Access the CPP/PNP PID. Verify that the CPP/PNP PID changes from Neutral to Drive when the neutral switch connector is disconnected. Does the CPP/PNP PID change from Neutral to Drive?	Yes	Go to the next step.
11		No	Go to Step 13.
12	INSPECT NEUTRAL SWITCH Disconnect the neutral switch connector. Inspect the neutral switch. (See NEUTRAL SWITCH INSPECTION ). Is there any malfunction?	Yes	Replace the neutral switch, then go to Step 14. (See NEUTRAL SWITCH REMOVAL/INSTALLATION ). (See NEUTRAL SWITCH REMOVAL/INSTALLATION ).
12		No	Go to Step 14.
13	INSPECT NEUTRAL SWITCH SIGNAL CIRCUIT FOR SHORT TO GROUND Disconnect the neutral switch and PCM connectors. Inspect for continuity between neutral switch terminal 2A (wiring harness-side) and body ground. Is there continuity?	Yes	Repair or replace the wiring harness for a possible short to ground, then go to the next step.
13		No	Go to the next step.
14	VERIFY TROUBLESHOOTING OF DTC P0850 COMPLETED Make sure to reconnect all disconnected connectors. Clear the DTC from the PCM memory using the MMDS. Start the engine. Drive the vehicle above 30 km/b {19 mph} and stop vehicle. Depress and release the clutch pedal more than 10 times during drive cycle. Is the PENDING CODE for this DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION ).
14		No	Go to the next step.
15	VERIFY AFTER REPAIR PROCEDURE Perform the "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE ). Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE ).
15		No	DTC troubleshooting completed.