Lexus IS250 IS220d GSE20 ALE20 - BRAKE CONTROL

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT BRAKE ACTUATOR ASSEMBLY

CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BRAKE ACTUATOR ASSEMBLY)

RECONFIRM DTC

DTC C1225/25 SM Solenoid Circuit

DESCRIPTION

DTC No.DTC Detection ConditionTrouble Area
C1225/25When any of the following is detected:
While switching solenoid (SM1 or SM2) ON is being output, overcurrent continues for 0.05 seconds or more.
While switching solenoid (SM1 or SM2) OFF is being output, an open circuit continues for 0.05 seconds or more.
While switching solenoid (SM1 or SM2) ON is being output, an open circuit continues for 0.1 seconds or more.
While switching solenoid (SM1 or SM2) OFF is being output, current continues to be applied for 0.1 seconds or more.
Short to GND in the switching solenoid (SM1 or SM2) continues for 0.1 seconds or more.
Switching solenoids SM1 and SM2 are shorted for 0.1 seconds or more.
SM1 or SM2 circuit
Skid control ECU

WIRING DIAGRAM

Dtc C1225/25  Sm Solenoid Circuit. BRAKE CONTROL. Lexus IS250 IS220d GSE20 ALE20

INSPECTION PROCEDURE

  • NOTICE:
  • When replacing the skid control ECU, perform zero point calibration and store system information .
1.INSPECT BRAKE ACTUATOR ASSEMBLY
Dtc C1225/25  Sm Solenoid Circuit. BRAKE CONTROL. Lexus IS250 IS220d GSE20 ALE20

Disconnect the brake actuator connector.

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

  • Standard resistance:
  • Tester ConnectionConditionSpecified Condition
    13 (SM1+) - 14 (SM1-)Always8.1 to 9.1 Ω
    at 25°C (77°F)
    14 (SM1-) - Body groundAlways10 kΩ or higher
    15 (SM2+) - 16 (SM2-)Always8.1 to 9.1 Ω
    at 25°C (77°F)
    16 (SM2-) - Body groundAlways10 kΩ or higher
NG
REPLACE BRAKE ACTUATOR ASSEMBLY
OK
2.CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BRAKE ACTUATOR ASSEMBLY)
Dtc C1225/25  Sm Solenoid Circuit. BRAKE CONTROL. Lexus IS250 IS220d GSE20 ALE20

Disconnect the skid control ECU connector.

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

  • Standard resistance:
  • Tester ConnectionConditionSpecified Condition
    J78-25 (SM1+) - A13-13 (SM1+)AlwaysBelow 1 Ω
    J78-25 (SM1+) - Body groundAlways10 kΩ or higher
    J78-12 (SM1-) - A13-14 (SM1-)AlwaysBelow 1 Ω
    J78-12 (SM1-) - Body groundAlways10 kΩ or higher
    J78-11 (SM2+) - A13-15 (SM2+)AlwaysBelow 1 Ω
    J78-11 (SM2+) - Body groundAlways10 kΩ or higher
    J78-24 (SM2-) - A13-16 (SM2-)AlwaysBelow 1 Ω
    J78-24 (SM2-) - Body groundAlways10 kΩ or higher
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
3.RECONFIRM DTC

Reconnect the skid control ECU connector and the brake actuator connector.

Clear the DTC .

Start the engine.

Check if the same DTC is recorded .

  • Result:
  • ConditionProceed to
    DTC (C1225/25) is not outputA
    DTC (C1225/25) is outputB
  • HINT:
If the normal system code is output (the trouble code is not output), slightly jiggle the connectors, wire harness, and fuses of the skid control ECU and brake actuator assembly. Make sure that no DTCs are output.
If any DTCs are output while jiggling a connector or wire harness of the skid control ECU and brake actuator assembly, inspect and repair the connector or wire harness.
B
REPLACE SKID CONTROL ECU
A
USE SIMULATION METHOD TO CHECK