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DTC    P0851-579    Park / Neutral Switch Input Circuit Low

DTC    P0852-580    Park / Neutral Switch Input Circuit High

for Preparation Click here


DESCRIPTION

  1. Instead of having a parking position as one of the positions of the conventional selector lever, a transmission shift main switch (P position switch) is provided independently above the selector lever. The switch is a momentary type, in which the button does not lock mechanically.
  2. The transmission shift main switch (P position switch) contains resistors R1 and R2. When the transmission shift main switch (P position switch) is not pressed, the switch provides a combined resistance of R1 and R2; and when the transmission shift main switch (P position switch) is pressed, the switch provides only the resistance of R1. The voltage at the P1 terminal of the power management control ECU (HV CPU) varies with the changes in the resistance of the switch. The power management control ECU (HV CPU) determines the transmission shift main switch (P position switch) operation according to this resistance signal.

DTC No.
INF Code
DTC Detection Condition
Trouble Area
P0851
579
GND short in P position switch circuit
  1. Wire harness or connector
  2. Transmission shift main switch (P position switch)
  3. Power management control ECU
P0852
580
Open or +B short in P position switch circuit

WIRING DIAGRAM


A216493E01

Refer to the wiring diagram for DTC P0AE6-225 (Click here).

INSPECTION PROCEDURE

1.INSPECT TRANSMISSION SHIFT MAIN SWITCH (P POSITION SWITCH)

  1. Disconnect connector b1 from the transmission shift main switch (P position switch).



    A216509E02

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Switch Condition
    		Specified Condition
    b1-4 (S) - b1-2 (E)
    		Switch pressed
    		680 Ω
    b1-4 (S) - b1-2 (E)
    		Switch released
    		4580 Ω

    Text in Illustration 
    *1
    		Component without harness connected
    (Transmission Shift Main Switch (P Position Switch))

    HINT:
    Terminals No. 1 and No. 8 on the component side connector are empty.

  1. Connect the transmission shift main switch (P position switch) connector.



NG
REPLACE TRANSMISSION SHIFT MAIN SWITCH
OK


2.CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - P POSITION SWITCH)

  1. Disconnect connector L5 from the power management control ECU.

  1. Disconnect connector b1 from the transmission shift main switch (P position switch).



    A217102E01

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance (Check for Open):
    Tester Connection
    		Switch Condition
    		Specified Condition
    L5-16 (P1) - b1-4 (S)
    		Power switch off
    		Below 1 Ω

    Standard Resistance (Check for Short):
    Tester Connection
    		Switch Condition
    		Specified Condition
    L5-16 (P1) or b1-4 (S) - Body ground and other terminals
    		Power switch off
    		10 kΩ or higher

    Text in Illustration 
    *1
    		Rear view of wire harness connector
    (to Power Management Control ECU)
    *2
    		Front view of wire harness connector
    (to Transmission Shift Main Switch (P Position Switch))

    HINT:
    As necessary, check that there is no short to power supply wires when performing the above wire harness inspection.

  1. Connect the transmission shift main switch (P position switch) connector.

  1. Connect the power management control ECU connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.CHECK HARNESS AND CONNECTOR (P POSITION SWITCH - BODY GROUND)

  1. Disconnect connector b1 from the transmission shift main switch (P position switch).



    C208992E02

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance (Check for Open):
    Tester Connection
    		Switch Condition
    		Specified Condition
    b1-2 (E) - Body ground
    		Power switch off
    		Below 1 Ω

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Transmission Shift Main Switch (P Position Switch))

  1. Connect the transmission shift main switch (P position switch) connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE POWER MANAGEMENT CONTROL ECU (Click here)