Parking Brake Switch Circuit [03/2019 - 11/2022]: Procedure

1. Choose the model to be inspected.

   Result

   Result	Proceed to
   w/ Electric Parking Brake System	A
   w/o Electric Parking Brake System	B

Result: 

B 

See step  4

Result: 

A 

See step  2

1. Check that the parking brake indicator comes on when the parking brake is applied and goes off when it is released.

   OK

   The parking brake indicator operates as specified above.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

GO TO ELECTRIC PARKING BRAKE SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [06/2018 - ] 

Result: 

OK 

See step  3

1. Disconnect the I56 radio and display receiver assembly connector.
2. Disconnect the A51 skid control ECU (brake actuator assembly) connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I56-20 (PKB) - A51-35 (PKB)	Always	Below 1 Ω
   I56-20 (PKB) or A51-35 (PKB) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

OK 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [03/2019 - 09/2019]  , or refer to  PROBLEM SYMPTOMS TABLE [09/2019 - 04/2020]  , or refer to  PROBLEM SYMPTOMS TABLE [04/2020 - 09/2022]  , or refer to  PROBLEM SYMPTOMS TABLE [09/2022 - 11/2022] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

1. Disconnect the I56 radio and display receiver assembly connector.
2. Disconnect the I122 parking brake switch assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I56-20 (PKB) - I122-1 (+)	Always	Below 1 Ω
   I56-20 (PKB) or I122-1 (+) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  5

1. Inspect the parking brake switch assembly.

   Refer to INSPECTION [01/2019 - 09/2022] , or refer to INSPECTION [09/2022 - ]

   Result

   Proceed to
   OK
   NG

Result: 

OK 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [03/2019 - 09/2019]  , or refer to  PROBLEM SYMPTOMS TABLE [09/2019 - 04/2020]  , or refer to  PROBLEM SYMPTOMS TABLE [04/2020 - 09/2022]  , or refer to  PROBLEM SYMPTOMS TABLE [09/2022 - 11/2022] 

Result: 

NG 

REPLACE PARKING BRAKE SWITCH ASSEMBLY. Refer to  REMOVAL [01/2019 - 09/2022]  , or refer to  REMOVAL [09/2022 - 11/2022]