Inspection Procedure

1. Check the information code from the FREEZE FRAME DATA  memorized when the DTC (C1377/43) is stored .

Result 

B: REPLACE BRAKE CONTROL POWER SUPPLY 

C:  Go to step  7

A: Go to next step 

1. Remove the ABS1 and ABS MAIN1 fuses from the engine room R/B (J/B) No.1.
2. Check the ABS1 and ABS MAIN1 fuses.

   Resistance: 

   Below 1 Ω. (Continuity) 

NG: REPLACE FUSE (ABS1 OR ABS MAIN1 FUSE) 

OK: Go to next step 

1. Disconnect the brake control power supply connector.
2. Measure the voltage according to the value(s) in the table below.

   Voltage 

   TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART
   
   

   Tester Connection	Specified Condition
   U27-8 (+BC) - Body ground	10 to 14 V

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

   Resistance 

   TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART
   
   

   Tester Connection	Specified Condition
   U27-14 (GND) - Body ground	Below 1 Ω

Fig 1: Identifying Brake Control Power Supply Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (+BC OR GND CIRCUIT) 

OK: Go to next step 

1. Disconnect the skid control ECU (A13, A15) connectors.
2. Measure the voltage according to the value(s) in the table below.

   Voltage 

   TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART
   
   

   Tester Connection	Specified Condition
   A13-39 (DI1) - Body ground	10 to 14 V
   A15-33 (DI2) - Body ground	10 to 14 V

Fig 2: Identifying Skid Control ECU (A13, A15) Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (DI CIRCUIT) 

OK: Go to next step 

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

   HINT:

   Perform inspection while the brake is not operated.

   Voltage 

   TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART
   
   

   Tester Connection	Specified Condition
   U27-1 (OUT1) - Body ground	10 to 14 V
   U27-2 (CTY+) - Body ground	10 to 14V ((1))
   U27-7 (OUT2) - Body ground	10 to 14 V
   (1) For 5 seconds after the driver's door is opened.

Fig 3: Identifying Brake Control Power Supply (Out Terminal)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK:  Go to step  9

NG: Go to next step 

1. Disconnect the skid control ECU (A13, A15) connectors and brake control power supply connector.
2. Measure the resistance according to the value(s) in the table below.

   Resistance 

   TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART
   
   

   Tester Connection	Specified Condition
   A13-13 (CTY+) - U27-2 (CTY+)	Below 1 Ω
   A13-21 (CBI1) - U27-1 (OUT1)	Below 1 Ω
   A15-35 (CBI2) - U27-7 (OUT2)	Below 1 Ω

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

   Resistance 

   TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART
   
   

   Tester Connection	Specified Condition
   A13-13 (CTY+) - Body ground	10 kΩ or higher
   A13-21 (CBI1) - Body ground	10 kΩ or higher
   A15-35 (CBI2) - Body ground	10 kΩ or higher

Fig 4: Identifying Skid Control ECU (A13, A15) And Brake Control Power Supply Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK:  Go to step  9

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

1. Check the battery voltage.

   Voltage: 

   11 to 14 V 

NG: INSPECT CHARGING SYSTEM 

OK: Go to next step 

1. Disconnect the brake control power supply connector.
2. Measure the voltage according to the value(s) in the table below.

   Voltage 

   TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART
   
   

   Tester Connection	Specified Condition
   U27-8 (+BC) - Body ground	10 to 14 V

Fig 5: Identifying Brake Control Power Supply Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (+BC CIRCUIT) 

OK: Go to next step 

1. Clear the DTC (see DTC CHECK / CLEAR ).
2. Turn the engine switch on (IG).
3. Check if the same DTC is recorded (see DTC CHECK / CLEAR ).

   HINT:

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

Result 

B: REPLACE BRAKE CONTROL POWER SUPPLY 

A: END