Nissan Maxima Service and Repair Manual: 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.

DTC Logic

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.INSPECTION START

2.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following 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.

3.CHECK PNP SIGNAL

With CONSULT

1. Turn ignition switch ON.
2. Select "P/N POSI SW" in "DATA MONITOR" mode with CONSULT. Then check the "P/N POSI SW" signal under the following conditions

4.PERFORM DTC CONFIRMATION PROCEDURE

1. Select "DATA MONITOR" mode with CONSULT.
2. Start engine and warm it up to normal operating temperature.
3. Maintain the following conditions for at least 50 consecutive seconds.
4. Check 1st trip DTC.

CAUTION: Always drive vehicle at a safe speed.

5.PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to EC-398, "Component Function Check".

NOTE: Use component function check to check the overall function of the park/neutral position (PNP) signal circuit.

During this check, a 1st trip DTC might not be confirmed.

Component Function Check

1.PERFORM COMPONENT FUNCTION CHECK

1. Turn ignition switch ON.
2. Check the voltage between ECM harness connectors.

Diagnosis Procedure

1.CHECK DTC WITH TCM

2.CHECK PNP SIGNAL CIRCUIT FOR OPEN AND SHORT-I

1. Turn ignition switch OFF.
2. Disconnect TCM harness connector.
3. Disconnect IPDM E/R harness connector.
4. Check the continuity between TCM harness connector and IPDM E/R harness connector.
5. Also check harness for short to ground and short to power.

3.CHECK PNP SIGNAL CIRCUIT FOR OPEN AND SHORT-II

1. Disconnect IPDM E/R harness connectors.
2. Disconnect ECM harness connector.
3. Check the continuity between ECM harness connector and IPDM E/R harness connector.
4. Also check harness for short to ground and short to power.

4.DETECT MALFUNCTIONING PART

Check the following.

• Junction block harness connectors E45, E50
• Harness for open or short between ECM and IPDM E/R

5.CHECK INTERMITTENT INCIDENT