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DTC    C1311/11    Open in Main Relay 1 Circuit

DTC    C1312/12    Short in Main Relay 1 Circuit

for Preparation Click here


DESCRIPTION

The ABS main relay supplies power to the changeover solenoid and the linear solenoid.
The ABS main relay remains on for approximately 2 minutes after the power switch is turned off and the input of brake pedal operation signals stops, and supplies power to the system to keep it ready to operate.

DTC Code
INF Code
DTC Detection Condition
Trouble Area
C1311/11
1
Either of the following is detected:
  1. When the power switch is on (READY):
    The ABS main relay contact is not turned ON (BS terminal voltage 3.5 V or more) for 0.2 seconds or more when ABS main relay ON is requested while IG1 terminal voltage is 9.5 V or more.
  2. When the power switch is off:
    The ABS main relay contact is not turned ON (BS terminal voltage 3.5 V or more) for 0.2 seconds or more when ABS main relay ON is requested.
  1. Open or short in ABS main relay circuit
  2. Brake booster with master cylinder (Skid control ECU)
C1312/12
2
The ABS main relay contact is turned ON (BS terminal voltage 3.5 V or more) for 4.5 seconds or more when ABS main relay OFF is requested from the ECU.
  1. Short in ABS main relay circuit
  2. ABS main relay internal stuck
  3. Brake booster with master cylinder (Skid control ECU)

WIRING DIAGRAM

Refer to DTCs C1241/41 and C1242/42 (Click here).

INSPECTION PROCEDURE

NOTICE:
When replacing the brake booster with master cylinder (skid control ECU), perform initialization, calibration of the linear solenoid valve and emergency brake signal learning (Click here).

1.PERFORM ACTIVE TEST USING INTELLIGENT TESTER (ABS MAIN RELAY)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Select the Active Test on the intelligent tester (Click here).

    ABS/VSC/TRC 
    Tester Display
    		Test Part
    		Control Range
    		Diagnostic Note
    ECB* Main Relay
    		ABS main relay
    		Relay ON/OFF
    		-
    *: Electronically Controlled Brake System

  1. Select the Data List on the intelligent tester (Click here).


ABS/VSC/TRC 
Tester Display
Measurement Item/Range
Normal Condition
Diagnostic Note
ECB* Main Relay
ABS main relay / ON or OFF
ON: Relay on
OFF: Relay off
-
*: Electronically Controlled Brake System

  1. Check the operating condition of the ABS main relay when operating it with the intelligent tester.

    Result:

    Result
    		Proceed to
    ABS main relay in the Data List turns ON/OFF using the Active Test
    		A
    ABS main relay in the Data List does not change using the Active Test
    		B



B
Go to step 4
A


2.INSPECT SKID CONTROL ECU (BS TERMINAL)


    C209401E07

  1. Turn the power switch off.

  1. Make sure that there is no looseness at the locking part and the connecting part of the connector.

  1. Disconnect the skid control ECU connector.

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    A58-15 (BS) - Body ground
    		Always
    		11 to 14 V

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Skid Control ECU)



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (BS CIRCUIT)
OK


3.RECONFIRM DTC

  1. Reconnect the skid control ECU connector.

  1. Clear the DTCs (Click here).

  1. Turn the power switch on (IG).

  1. Check if the same DTC is recorded (Click here).

    Result:

    Result
    		Proceed to
    DTCs (C1311/11and C1312/12) are not output
    		A
    DTCs (C1311/11 and/or C1312/12) are output (for LHD)
    		B
    DTCs (C1311/11 and/or C1312/12) are output (for RHD)
    		C



B
REPLACE BRAKE BOOSTER WITH MASTER CYLINDER (Click here)

C
REPLACE BRAKE BOOSTER WITH MASTER CYLINDER (Click here)
A

CHECK FOR INTERMITTENT PROBLEMS (Click here)  

4.INSPECT ABS MAIN FUSES
C210280E01

  1. Turn the power switch off.

  1. Remove the ABS MAIN fuses from the engine room relay block.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    ABS MAIN NO. 1 (20 A) fuse
    		Always
    		Below 1 Ω
    ABS MAIN NO. 2 (7.5 A) fuse
    		Always
    		Below 1 Ω

    Text in Illustration 
    *1
    		Engine Room Relay Block
    *2
    		ABS MAIN NO. 1 Fuse
    *3
    		ABS MAIN NO. 2 Fuse



NG
REPLACE ABS MAIN FUSES
OK


5.INSPECT SKID CONTROL ECU (BI TERMINAL)


    C209401E08

  1. Install the ABS MAIN fuses.

  1. Make sure that there is no looseness at the locking part and the connecting part of the connector.

  1. Disconnect the skid control ECU connector.

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    A58-14 (BI) - Body ground
    		Always
    		11 to 14 V

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Skid Control ECU)



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (BI CIRCUIT)
OK


6.INSPECT SKID CONTROL ECU (BS TERMINAL)


    C209401E07

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    A58-15 (BS) - Body ground
    		Always
    		11 to 14 V

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Skid Control ECU)

    Result:

    Result
    		Proceed to
    OK (for LHD)
    		A
    OK (for RHD)
    		B
    NG
    		C



B
REPLACE BRAKE BOOSTER WITH MASTER CYLINDER (Click here)

C
REPAIR OR REPLACE HARNESS OR CONNECTOR (BS CIRCUIT)
A

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER (Click here)