DTC P0851: Park / Neutral Switch Input Circuit Low; DTC P0852: Park / Neutral Switch Input Circuit High [06/2016 - 12/2017]: Procedure

1. Confirm the transmission.
   RESULT
   
   

   Result	Proceed to
   Manual Transmission	A
   Automatic Transmission	B

Result: 

B 

See step  5

Result: 

A 

See step  2

1. Disconnect the neutral position switch connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

2. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   A54-1 - A54-2	Ignition switch ON	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Neutral Position Switch)

Result: 

NG 

See step  4

Result: 

OK 

See step  3

1. Inspect the neutral position switch (Refer to INSPECTION [06/2016 - ] ).

Result: 

OK 

CHECK FOR INTERMITTENT PROBLEMS 

(Refer to CHECK FOR INTERMITTENT PROBLEMS [06/2016 - ] )

Result: 

NG 

REPLACE NEUTRAL POSITION SWITCH 

(Refer to REMOVAL [06/2016 - ] )

1. Disconnect the ECM connector.
2. Disconnect the neutral position switch connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance (Check for open)

   Tester Connection	Condition	Specified Condition
   A33-16 (NSW) - A54-2	Always	Below 1 Ω
   A33-4 (EC) - A54-1	Always	Below 1 Ω

   Standard Resistance (Check for short)

   Tester Connection	Condition	Specified Condition
   A33-16 (NSW) or A54-2 - Body ground	Always	10 kΩ or higher
   A33-4 (EC) or A54-1 - Body ground	Always	10 kΩ or higher

Result: 

OK 

REPLACE ECM 

(Refer to REMOVAL [06/2016 - ] )

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

1. Disconnect the park/neutral position switch assembly connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

2. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   L2-4 - L2-5	Ignition switch ON	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Park/Neutral Position Switch Assembly)

Result: 

NG 

See step  7

Result: 

OK 

See step  6

1. Inspect the park/neutral position switch assembly (Refer to INSPECTION [06/2016 - ] ).

Result: 

OK 

CHECK FOR INTERMITTENT PROBLEMS 

(Refer to CHECK FOR INTERMITTENT PROBLEMS [06/2016 - ] )

Result: 

NG 

REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY 

(Refer to REMOVAL [06/2016 - ] )

1. Disconnect the ECM connector.
2. Disconnect the park/neutral position switch assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance (Check for open)

   Tester Connection	Condition	Specified Condition
   A33-16 (NSW) - L2-4	Always	Below 1 Ω
   L2-5 - Body ground	Always	Below 1 Ω

   Standard Resistance (Check for short)

   Tester Connection	Condition	Specified Condition
   A33-16 (NSW) or L2-4 - Body ground	Always	10 kΩ or higher

Result: 

OK 

REPLACE ECM 

(Refer to REMOVAL [06/2016 - ] )

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR