Diagnostic trouble code C0226 C0236 C0246 C0256 Lexus IS250

Description

Wiring diagram

Inspection procedure

INSPECT BRAKE ACTUATOR ASSEMBLY

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

RECONFIRM DTC

DTC C0226/21 SFR Solenoid Circuit

DTC C0236/22 SFL Solenoid Circuit

DTC C0246/23 SRR Solenoid Circuit

DTC C0256/24 SRL Solenoid Circuit

Description

These solenoids turn on when signals are received from the skid control ECU and control the pressure acting on the wheel cylinders to control the braking force.  

DTC No.	DTC Detection Condition	Trouble Area
C0226/21 C0236/22 C0246/23 C0256/24	When any of the following is detected: Open or short in the solenoid circuit continues for 0.05 seconds or more. While solenoid OFF is being output, an open circuit continues for 0.05 seconds or more. While solenoid ON is being output, overcurrent continues for 0.05 seconds or more. While solenoid ON is being output, an open circuit continues for 0.1 seconds or more. While solenoid OFF is being output, current continues to be applied for 0.1 seconds or more. Short to GND in the solenoid continues for 0.1 seconds or more.	Solenoid circuit Skid control ECU

Wiring diagram

Inspection procedure

NOTICE:

When replacing the skid control ECU, perform zero point calibration and store system information ( ).

HINT:

When C0278/11 or C0279/12 is output together with C0226/21, C0236/22, C0246/23, or C0256/24, inspect and repair the trouble areas indicated by C0278/11 or C0279/12 first.

 

1.INSPECT BRAKE ACTUATOR ASSEMBLY

1. Disconnect the brake actuator connector.

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

Standard resistance:

Tester Connection	Condition	Specified Condition
31 (BS) - 9 (SFRR)	Always	4.0 to 4.6 ? at 25°C (77°F)
9 (SFRR) - Body ground	Always	10 k? or higher
31 (BS) - 10 (SFLR)	Always	4.0 to 4.6 ? at 25°C (77°F)
10 (SFLR) - Body ground	Always	10 k? or higher
31 (BS) - 11 (SRRR)	Always	4.0 to 4.6 ? at 25°C (77°F)
11 (SRRR) - Body ground	Always	10 k? or higher
31 (BS) - 12 (SRLR)	Always	4.0 to 4.6 ? at 25°C (77°F)
12 (SRLR) - Body ground	Always	10 k? or higher
33 (FRA+) - 34 (FRA-)	Always	4.8 to 5.4 ? at 25°C (77°F)
34 (FRA-) - Body ground	Always	10 k? or higher
35 (FLA+) - 36 (FLA-)	Always	4.8 to 5.4 ? at 25°C (77°F)
36 (FLA-) - Body ground	Always	10 k? or higher
4 (RRA+) - 5 (RRA-)	Always	4.8 to 5.4 ? at 25°C (77°F)
5 (RRA-) - Body ground	Always	10 k? or higher
6 (RLA+) - 8 (RLA-)	Always	4.8 to 5.4 ? at 25°C (77°F)
8 (RLA-) - Body ground	Always	10 k? or higher

NG	REPLACE BRAKE ACTUATOR ASSEMBLY

OK

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

1. Disconnect the skid control ECU connector.

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

Standard resistance:

LHD:

Tester Connection	Condition	Specified Condition
A35-1 (SFRR) - A13-9 (SFRR)	Always	Below 1 ?
A35-1 (SFRR) - Body ground	Always	10 k? or higher
A35-13 (SFLR) - A13-10 (SFLR)	Always	Below 1 ?
A35-13 (SFLR) - Body ground	Always	10 k? or higher
A35-12 (SRRR) - A13-11 (SRRR)	Always	Below 1 ?
A35-12 (SRRR) - Body ground	Always	10 k? or higher
A35-2 (SRLR) - A13-12 (SRLR)	Always	Below 1 ?
A35-2 (SRLR) - Body ground	Always	10 k? or higher
J78-23 (FRA+) - A13-33 (FRA+)	Always	Below 1 ?
J78-23 (FRA+) - Body ground	Always	10 k? or higher
J78-10 (FRA-) - A13-34 (FRA-)	Always	Below 1 ?
J78-10 (FRA-) - Body ground	Always	10 k? or higher
J78-21 (FLA+) - A13-35 (FLA+)	Always	Below 1 ?
J78-21 (FLA+) - Body ground	Always	10 k? or higher
J78-8 (FLA-) - A13-36 (FLA-)	Always	Below 1 ?
J78-8 (FLA-) - Body ground	Always	10 k? or higher
J78-7 (RRA+) - A13-4 (RRA+)	Always	Below 1 ?
J78-7 (RRA+) - Body ground	Always	10 k? or higher
J78-20 (RRA-) - A13-5 (RRA-)	Always	Below 1 ?
J78-20 (RRA-) - Body ground	Always	10 k? or higher
J78-9 (RLA+) - A13-6 (RLA+)	Always	Below 1 ?
J78-9 (RLA+) - Body ground	Always	10 k? or higher
J78-22 (RLA-) - A13-8 (RLA-)	Always	Below 1 ?
J78-22 (RLA-) - Body ground	Always	10 k? or higher

RHD:

Tester Connection	Condition	Specified Condition
J98-1 (SFRR) - A13-9 (SFRR)	Always	Below 1 ?
J98-1 (SFRR) - Body ground	Always	10 k? or higher
J98-13 (SFLR) - A13-10 (SFLR)	Always	Below 1 ?
J98-13 (SFLR) - Body ground	Always	10 k? or higher
J98-12 (SRRR) - A13-11 (SRRR)	Always	Below 1 ?
J98-12 (SRRR) - Body ground	Always	10 k? or higher
J98-2 (SRLR) - A13-12 (SRLR)	Always	Below 1 ?
J98-2 (SRLR) - Body ground	Always	10 k? or higher
J78-23 (FRA+) - A13-33 (FRA+)	Always	Below 1 ?
J78-23 (FRA+) - Body ground	Always	10 k? or higher
J78-10 (FRA-) - A13-34 (FRA-)	Always	Below 1 ?
J78-10 (FRA-) - Body ground	Always	10 k? or higher
J78-21 (FLA+) - A13-35 (FLA+)	Always	Below 1 ?
J78-21 (FLA+) - Body ground	Always	10 k? or higher
J78-8 (FLA-) - A13-36 (FLA-)	Always	Below 1 ?
J78-8 (FLA-) - Body ground	Always	10 k? or higher
J78-7 (RRA+) - A13-4 (RRA+)	Always	Below 1 ?
J78-7 (RRA+) - Body ground	Always	10 k? or higher
J78-20 (RRA-) - A13-5 (RRA-)	Always	Below 1 ?
J78-20 (RRA-) - Body ground	Always	10 k? or higher
J78-9 (RLA+) - A13-6 (RLA+)	Always	Below 1 ?
J78-9 (RLA+) - Body ground	Always	10 k? or higher
J78-22 (RLA-) - A13-8 (RLA-)	Always	Below 1 ?
J78-22 (RLA-) - Body ground	Always	10 k? or higher

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3.RECONFIRM DTC

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

2. Clear the DTC .

3. Start the engine.

4. Check if the same DTC is recorded .

Result:

Condition	Proceed to
DTCs (C0226/21, C0236/22, C0246/23, and/or C0256/24) are not output	A
DTCs (C0226/21, C0236/22, C0246/23, and/or C0256/24) are output	B

HINT:

1. 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.
2. 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