DTC P0851-579: Park / Neutral Switch Input Circuit Low; DTC P0852-580: Park / Neutral Switch Input Circuit High [11/2014 - ]: Procedure

1. Disconnect connector L124 from the P position switch (transmission shift main switch).
2. Measure the resistance according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   L124-4 (S) - L124-2 (E)	Switch pressed	680 Ω
   L124-4 (S) - L124-2 (E)	Switch released	4580 Ω

   TEXT IN ILLUSTRATION
   
   

   *a	Component without harness connected (P Position Switch (Transmission Shift Main Switch))

   HINT: 

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

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

NG → REPLACE P POSITION SWITCH 

OK: Go to next step 

1. Disconnect connector L5 from the power management control ECU.
2. Disconnect connector L124 from the P position switch (transmission shift main switch).
3. Measure the resistance according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Resistance (Check for Open)

   Tester Connection	Switch Condition	Specified Condition
   L5-16 (P1) - L124-4 (S)	Power switch off	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Switch Condition	Specified Condition
   L5-16 (P1) or L124-4 (S) - Body ground and other terminals	Power switch off	10 kΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *a	Rear view of wire harness connector (to Power Management Control ECU)
   *b	Front view of wire harness connector (to P Position Switch (Transmission Shift Main Switch))

   HINT: 

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

4. Connect the P position switch (transmission shift main switch) connector.
5. Connect the power management control ECU connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Disconnect connector L124 from the P position switch (transmission shift main switch).
2. Measure the resistance according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Resistance (Check for Open)

   Tester Connection	Switch Condition	Specified Condition
   L124-2 (E) - Body ground	Power switch off	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to P Position Switch (Transmission Shift Main Switch))

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

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   4