FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P0850


P0850 PNP SWITCH





Description
When the selector lever position is P or N, park/neutral position (PNP) signal from the TCM is sent to ECM.(A/
T models)
When the selector lever position is Neutral position, park/neutral position (PNP) switch is ON.(M/T models)
ECM detects the position because the continuity of the line (the ON signal) exists.




DTC Logic

DTC DETECTION LOGIC






DTC CONFIRMATION PROCEDURE
1.INSPECTION START
Do you have CONSULT-III?
Do you have CONSULT-III?
YES - GO TO 2.
NO - GO TO 5.
2.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
- GO TO 3.
3.CHECK PNP SWITCH SIGNAL (M/T) OR TRANSMISSION RANGE SWITCH SIGNAL (A/T)
With CONSULT-III
1. Turn ignition switch ON.
2. Select "P/N POSI SW" in "DATA MONITOR" mode with CONSULT-III. Then check the "P/N POSI SW" signal under the following conditions.





Is the inspection result normal?
YES - GO TO 4.
NO - Go to SEE Diagnosis Procedure.
4.PERFORM DTC CONFIRMATION PROCEDURE
1. Select "DATA MONITOR" mode with CONSULT-III.
2. Start engine and warm it up to normal operating temperature.
3. Maintain the following conditions for at least 50 consecutive seconds.

CAUTION:
Always drive vehicle at a safe speed.





4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES - Go to SEE Diagnosis Procedure.
NO - INSPECTION END
5.PERFORM COMPONENT FUNCTION CHECK
Perform component function check. SEE Component Function Check.

NOTE:
Use component function check the overall function of the park/neutral position (PNP) signal circuit. During this check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES - INSPECTION END
NO - Go to SEE Diagnosis Procedure.




Component Function Check
1.PERFORM COMPONENT FUNCTION CHECK
1. Turn ignition switch ON.
2. Check the voltage between ECM harness connector terminals under the following conditions.





Is the inspection result normal?
YES - INSPECTION END
NO - Go to SEE Diagnosis Procedure.




Diagnosis Procedure
1.INSPECTION START
Check which type of transmission the vehicle is equipped with.
Which type of transmission?
A/T - GO TO 2.
M/T - GO TO 7.
2.CHECK DTC WITH TCM
Reading and Clearing Diagnostic Trouble Codes.
Is the inspection result normal?
YES - GO TO 3.
NO - Repair or replace.
3.CHECK STARTING SYSTEM
Turn ignition switch OFF, then turn it to START.
Does starter motor operate?
YES - GO TO 4.
NO - Check DTC with BCM. Signal Buffer.
4.CHECK TRANSMISSION RANGE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect A/T assembly harness connector.
3. Disconnect ECM harness connector.
4. Check the continuity between A/T assembly harness connector and ECM harness connector.





5. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES - GO TO 6.
NO - GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors F1, E3
- Harness connectors E106, M6
- Harness for open or short between A/T assembly and ECM
- Repair open circuit, short to ground or short to power in harness or connectors.
6.CHECK INTERMITTENT INCIDENT
Intermittent Incident.
- INSPECTION END
7.CHECK PNP SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect park/neutral position (PNP) switch harness connector.
3. Turn ignition switch ON.
4. Check the voltage between PNP switch harness connector and ground.





Is the inspection result normal?
YES - GO TO 9.
NO - GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E3, F1
- 10 A fuse (No. 43)
- IPDM E/R harness connector E7
- Harness for open or short between PNP switch and fuse
- Repair open circuit, short to ground or short to power in harness or connectors.
9.CHECK PNP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between PNP switch harness connector and ECM harness connector.





4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES - GO TO 11.
NO - GO TO 10.
10.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors F103, M116
- Harness for open or short between PNP switch and ECM
- Repair open circuit, short to ground or short to power in harness or connectors.
11.CHECK PNP SWITCH
Component Tests and General Diagnostics.
Is the inspection result normal?
YES - GO TO 12.
NO - Replace PNP switch.
12.CHECK INTERMITTENT INCIDENT
Intermittent Incident.
Is the inspection result normal?
YES - Replace IPDM E/R. Service and Repair.
NO - Repair or replace.