Electronically Controlled Brake System

BRAKE CONTROL: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: U0073/94, U0123/62, U0124/95, U0126/63, U0293/59: Control Module Communication Bus OFF
U0293/59 - Communication Error from HV ECU

DESCRIPTION

The skid control ECU receives the signals from the hybrid vehicle control ECU, the steering angle sensor, and the yaw rate and acceleration sensor via the CAN communication system.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

(a) Using the Techstream, check for any momentary interruptions in the wire harness and connector corresponding to a DTC Check For Intermittent Problems.

ABS/VSC/TRAC





Result:





HINT
Perform the above inspection before removing any sensor or connector.

C -- REPAIR OR REPLACE HARNESS OR CONNECTOR

B -- RECONFIRM DTC
A -- Continue to next step.

2. CHECK IF EACH SENSOR AND ECU CONNECTOR IS SECURELY CONNECTED

(a) Turn the ignition switch off.

(b) Check if each sensor and ECU connector is securely connected.

OK:

Each sensor and ECU connector is securely connected.

NG -- CONNECT CONNECTOR TO EACH SENSOR OR ECU CORRECTLY
OK -- Continue to next step.

3. RECONFIRM DTC

(a) Turn the ignition switch off.

(b) Record the output DTCs (for ABS, VSC, electronically controlled brake system, and/or CAN communication system) [ABS, VSC and/or electronically controlled brake system: Reading and Clearing Diagnostic Trouble Codes, CAN communication system (w/ Smart Key System): Diagnosis System, CAN communication system (w/o Smart Key System): Diagnosis System].

HINT
If the CAN communication system DTC and the relevant sensor DTCs are output simultaneously, troubleshoot the relevant sensor DTCs (for ABS, VSC and/or electronically controlled brake system) after the CAN communication system returns to normal.

Result:





D -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How to Proceed With Troubleshooting

C -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How to Proceed With Troubleshooting

B -- REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Electronically Controlled Brake System

A -- CHECK FOR INTERMITTENT PROBLEMS How To Proceed With Troubleshooting

4. REPAIR OR REPLACE HARNESS OR CONNECTOR

(a) Turn the ignition switch off.

(b) Repair or replace the harness or connector.

(c) Check for any momentary interruption between the skid control ECU and each sensor or ECU Check For Intermittent Problems.

(d) Confirm that there are no momentary interruptions.

NEXT -- Continue to next step.

5. RECONFIRM DTC

(a) Turn the ignition switch off.

(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

(c) Turn the ignition switch to ON (READY).

(d) Drive the vehicle at a speed of 15 km/h (9 mph) or more and turn the steering wheel to the right and left.

(e) Check that no CAN communication system DTC is output (w/ Smart Key System: Diagnosis System, w/o Smart Key System: Diagnosis System).

(f) If ABS, VSC and/or electronically controlled brake system DTCs are output, record them Reading and Clearing Diagnostic Trouble Codes.

Result:





HINT
The CAN communication system must be normal when troubleshooting each sensor DTC (for ABS, VSC and/or electronically controlled brake system).

D -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How to Proceed With Troubleshooting

C -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How to Proceed With Troubleshooting

B -- REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Electronically Controlled Brake System

A -- END