DTC B1C57
DTC B1C57 : Front passenger's heater thermistor circuit open
| DTC Description | DTC |
|---|---|
| B1C57 Front passenger's heater thermistor circuit open |
DTC (Front Seat Heater Control Unit)
- If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A - Refer to: Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode A - Initial Communication and DTC Checks (2014 2015 2016), or Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode A - Initial Communication and DTC Checks (2017 2018 2019 2020) .
- The seat heater control unit does not turn on the seat heater until the seat core temperature is 85 degrees or less. Make sure the seat core temperature is below 85 degrees before troubleshooting.
- Problem verification
-1. Clear the DTCs with the HDS.
- 2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.
- 3. Wait for at least 90 seconds.
- 4. Check for DTCs with the HDS.
DTC Description DTC B1C57 Front passenger's heater thermistor circuit open Is DTC B1C57 indicated?
YES
Go to step 2.
NO
Intermittent failure, the system is OK at this time. Check for loose or poor connections.
- Seat heater check 1
-1. Disconnect the following connector.
Front seat heater control unit 14P connector - 2. Measure the resistance between test points 1 and 2, refer to the following table.
Test condition Vehicle OFF (LOCK) mode. Front seat heater control unit 14P connector: disconnected Test circuit ASTH+, ASTH Test point 1 Front seat heater control unit 14P connector No. 12 (BRN) Test point 2 Front seat heater control unit 14P connector No. 6 (GRN) Is resistance value within the range?
YES
Replace the front seat heater control unit .
NO
Go to step 3.
- Seat heater check 2
-1. Disconnect the following connector.
Front passenger's seat heater connector A (5P) - Refer to: Seat Heater Replacement (2017 2018 2019 2020), or Seat Heater Replacement (Seat Heaters), or Seat Heater Replacement - Ventilated Seats (Ventilated Seats) - 2. Measure the resistance between test points 1 and 2, refer to the following table.
Test condition Vehicle OFF (LOCK) mode. Front seat heater control unit 14P connector: disconnected. Front passenger's seat heater connector A (5P): disconnected Test circuit ASTH+, ASTH Test point 1 Front passenger's seat heater connector A (5P) No. 3 Test point 2 Front passenger's seat heater connector A (5P) No. 2 Is resistance value within the range?
YES
Replace the front seat heater control unit .
NO
Go to step 4.
- Open wire check (TH+ line)
-1. Connect terminals A and B with a jumper wire.
Terminal A Front passenger's seat heater connector A (5P) No. 3 (WHT) Terminal B Body ground - 2. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode. Front seat heater control unit 14P connector: disconnected. Front passenger's seat heater connector A (5P): disconnected Test circuit ASTH+ Test point 1 Front seat heater control unit 14P connector No. 12 (BRN) Test point 2 Body ground Is there continuity?
YES
Repair an open or high resistance in the ASTH wire.
NO
Repair an open or high resistance in the ASTH+ wire.