P0850

A761E AUTOMATIC TRANSMISSION: AUTOMATIC TRANSMISSION SYSTEM: P0705: Transmission Range Sensor Circuit Malfunction (PRNDL Input)

DTC P0705 - Transmission Range Sensor Circuit Malfunction (PRNDL Input)

DTC P0850 - Park / Neutral Switch Input Circuit

DESCRIPTION

The Park/Neutral Position (PNP) switch detects the shift lever position and sends signals to the ECM.






MONITOR DESCRIPTION

These DTCs indicate a problem with the park/neutral position switch or the wire harness in the park/neutral position switch circuit.
The park/neutral position switch detects the shift lever position and sends a signal to the ECM.
For security, the park/neutral position switch detects the shift lever position so that the engine can be started only when the shift lever is on P or N.
The park/neutral position switch sends a signal to the ECM according to the shift lever position (P, R, N, D or S).
The ECM determines that there is a problem with the switch or related parts if it receives more than 1 position signal simultaneously. The ECM will illuminate the MIL and store the DTC.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS

All





P0705





P0850





TYPICAL MALFUNCTION THRESHOLDS

P0705
- One of the following conditions is met: Condition (A), (B), (C) or (D)

Condition (A)

When 2 or more of the following signals are input at the same time






P0850






COMPONENT OPERATING RANGE

P0705





P0850





WIRING DIAGRAM





INSPECTION PROCEDURE
HINT: Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading the Data List information early in troubleshooting is one way to save diagnostic time.
NOTE:
In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a part is faulty or not.

1 Connect the Techstream to the DLC3.
2 Turn the ignition switch to ON.
3 Turn the Techstream on.
4 Enter the following menus: Powertrain / Engine and ECT / Data List.
5 According to the display on the Techstream, read the Data List.

Engine and ECT





PROCEDURE

1. INSPECT PARK/NEUTRAL POSITION SWITCH




(a) Disconnect the P1 park/neutral position switch connector.
(b) Measure the resistance of the park/neutral position switch when the shift lever is moved to each position.
Standard resistance:






NG -- REPLACE PARK/NEUTRAL POSITION SWITCH
OK -- Continue to next step.
2. INSPECT TRANSMISSION CONTROL SWITCH




(a) Disconnect the T29 switch connector.
(b) Measure the resistance of the switch when the shift lever is moved to each position.
Standard resistance:






NG -- REPLACE TRANSMISSION CONTROL SWITCH
OK -- Continue to next step.
3. CHECK WIRE HARNESS (ECM - BATTERY)
(a) Turn the ignition switch ON.




(b) Measure the voltage of the wire harness side connectors.
Standard voltage:





HINT: *: The voltage will drop slightly due to the turning on of the back up light.

NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- REPLACE ECM