ELECTRONICALLY CONTROLLED BRAKE SYSTEM, Diagnostic DTC:C1341/62, C1342/63, C1343/64, C1344/65

DESCRIPTION

The skid control ECU inputs the operating fluid pressure of each wheel cylinder using the wheel cylinder pressure sensors in order to control the braking force of each wheel.

DTCs may be stored if brake fluid leaks, a wheel cylinder vibrates due to uneven wear of the brake disc rotor, or foreign matter enters the solenoid valve.

DTCs may be stored if the line pressure drops during air bleeding or brake pad is replaced.

WIRING DIAGRAM

Refer to DTCs C1315/31, C1316/32, C1352/21, C1353/23, C1354/25, C1355/27, C1356/22, C1357/24, C1358/26 and C1359/28 Click here.

INSPECTION PROCEDURE

PROCEDURE

1. CHECK BRAKE FLUID LEAKAGE

   
   

   1. Check that there is no fluid leakage in the brake line between the brake actuator and the wheel cylinder which is the cause of DTCs.

   2. Check for a brake fluid leak from the connection between the accumulator pump and brake actuator Click here.

   3. Check that the brake is not dragging.

      OK
      There is no fluid leakage or dragging.

   
   

   NG

   REPAIR OR REPLACE APPLICABLE PART

   OK

2. PERFORM AIR BLEED

   
   

   1. Bleed the air from the front and rear brake systems Click here.

   
   

   NEXT

3. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BODY GROUND)

   
   

   1. Disconnect the A19 and A21 ECU connectors.

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

      Standard resistance

      Tester Connection Condition Specified Condition A19-17 (FRA+) - Body ground Always 10 kΩ or higher A19-18 (FRA-) - Body ground Always 10 kΩ or higher A19-4 (FRR+) - Body ground Always 10 kΩ or higher A19-3 (FRR-) - Body ground Always 10 kΩ or higher A19-19 (RLA+) - Body ground Always 10 kΩ or higher A19-20 (RLA-) - Body ground Always 10 kΩ or higher A19-34 (RLR+) - Body ground Always 10 kΩ or higher A19-33 (RLR-) - Body ground Always 10 kΩ or higher A21-17 (FLA+) - Body ground Always 10 kΩ or higher A21-18 (FLA-) - Body ground Always 10 kΩ or higher A21-4 (FLR+) - Body ground Always 10 kΩ or higher A21-3 (FLR-) - Body ground Always 10 kΩ or higher A21-20 (RRA+) - Body ground Always 10 kΩ or higher A21-21 (RRA-) - Body ground Always 10 kΩ or higher A21-34 (RRR+) - Body ground Always 10 kΩ or higher A21-33 (RRR-) - Body ground Always 10 kΩ or higher

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

4. CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR - BODY GROUND)

   
   

   1. Disconnect the A27 actuator connector.

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

      Standard resistance
      for LHD
      Tester Connection Condition Specified Condition A27-5 (FRA-) - Body ground Always 10 kΩ or higher A27-6 (SMC2) - Body ground Always 10 kΩ or higher A27-7 (BS2) - Body ground Always 10 kΩ or higher A27-8 (FRA+) - Body ground Always 10 kΩ or higher A27-9 (RLA-) - Body ground Always 10 kΩ or higher A27-10 (RLA+) - Body ground Always 10 kΩ or higher A27-11 (RRA-) - Body ground Always 10 kΩ or higher A27-12 (RRA+) - Body ground Always 10 kΩ or higher A27-13 (FLA+) - Body ground Always 10 kΩ or higher A27-14 (FLA-) - Body ground Always 10 kΩ or higher A27-19 (BS1) - Body ground Always 10 kΩ or higher A27-20 (SMC1) - Body ground Always 10 kΩ or higher A27-21 (FRR-) - Body ground Always 10 kΩ or higher A27-22 (FRR+) - Body ground Always 10 kΩ or higher A27-23 (RLR-) - Body ground Always 10 kΩ or higher A27-24 (RLR+) - Body ground Always 10 kΩ or higher A27-25 (RRR-) - Body ground Always 10 kΩ or higher A27-26 (RRR+) - Body ground Always 10 kΩ or higher A27-27 (FLR+) - Body ground Always 10 kΩ or higher A27-28 (FLR-) - Body ground Always 10 kΩ or higher
      for RHD
      Tester Connection Condition Specified Condition A27-43 (FRA-) - Body ground Always 10 kΩ or higher A27-19 (SMC2) - Body ground Always 10 kΩ or higher A27-20 (BS2) - Body ground Always 10 kΩ or higher A27-44 (FRA+) - Body ground Always 10 kΩ or higher A27-42 (RLA-) - Body ground Always 10 kΩ or higher A27-41 (RLA+) - Body ground Always 10 kΩ or higher A27-40 (RRA-) - Body ground Always 10 kΩ or higher A27-39 (RRA+) - Body ground Always 10 kΩ or higher A27-35 (FLA+) - Body ground Always 10 kΩ or higher A27-38 (FLA-) - Body ground Always 10 kΩ or higher A27-36 (BS1) - Body ground Always 10 kΩ or higher A27-37 (SMC1) - Body ground Always 10 kΩ or higher A27-27 (FRR-) - Body ground Always 10 kΩ or higher A27-28 (FRR+) - Body ground Always 10 kΩ or higher A27-26 (RLR-) - Body ground Always 10 kΩ or higher A27-25 (RLR+) - Body ground Always 10 kΩ or higher A27-24 (RRR-) - Body ground Always 10 kΩ or higher A27-23 (RRR+) - Body ground Always 10 kΩ or higher A27-21 (FLR+) - Body ground Always 10 kΩ or higher A27-22 (FLR-) - Body ground Always 10 kΩ or higher

   
   

   NG

   REPLACE HARNESS AND CONNECTOR

   OK

5. PERFORM ACTIVE TEST USING PRESSURE SENSOR OPERATION

   
   

   1. Check the pressure sensor operation Click here for LHD, Click here for RHD).

   
   

   NG

   REPLACE BRAKE ACTUATOR Click here

   OK

6. RECONFIRM DTC

   
   

   1. Clear the DTCs Click here.

   2. Repeat the braking test under malfunction conditions recreated based on the "FREEZE FRAME DATA" Click here.

   3. Check if the same DTCs are recorded Click here.

      Tech Tips

      Reinstall the sensors, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.

      Result

      Result	Proceed to
      DTCs (C1341/62, C1342/63, C1343/64 and C1344/65) are not output	A
      DTCs (C1341/62, C1342/63, C1343/64 and C1344/65) are output	B

   
   

   B

   REPLACE BRAKE ACTUATOR Click here

   A

   END