C1344
BRAKE CONTROL: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: C1341/62: Front Hydraulic System RH Malfunction
DTC C1341/62 - Front Hydraulic System RH Malfunction
DTC C1342/63 - Front Hydraulic System LH Malfunction
DTC C1343/64 - Rear Hydraulic System RH Malfunction
DTC C1344/65 - Rear Hydraulic System LH Malfunction
DESCRIPTION
The skid control ECU controls braking force according to the hybrid control system regenerative braking force and inputs the hydraulic pressure necessary for operating each wheel cylinder according to the wheel cylinder pressure sensor.
DTCs may be stored if one of the following occurs:
- Brake fluid leaks.
- Wheel cylinder vibrates due to uneven wear of a brake rotor.
- Foreign matter enters solenoid valve.
- Line pressure drops during air bleeding.
- Brake pad is replaced.
- Rotor is replaced.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTE: When replacing the brake actuator assembly, perform initialization and calibration of the linear solenoid valve. Initialization
HINT: When C1364/61 is output together with C1341/62, C1342/63, C1343/64 and/or C1344/65, inspect and repair the trouble areas indicated by C1364/61 first C1246.
PROCEDURE
1. CHECK FOR FLUID LEAK
(a) Check that there is no fluid leakage in the brake line between the brake actuator and the wheel cylinder which is indicated by DTCs.
(b) Check that the brake is not dragging.
OK:
There is no fluid leakage or dragging.
NG -- REPAIR OR REPLACE APPLICABLE PART
OK -- Continue to next step.
2. PERFORM AIR BLEEDING
(a) Bleed the air from the front and rear brake systems.
NEXT -- Continue to next step.
3. RECONFIRM DTC
(a) Clear the DTCs.
(b) Perform a road test under malfunction conditions recreated based on the Freeze Frame Data or customer problem analysis.
(c) Check if the same DTC is recorded.
Result:
HINT: DTCs may be stored if foreign matter or air enters the solenoid valves.
B -- END
A -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BODY GROUND)
(a) Turn the power switch off.
(b) Make sure that there is no looseness at the locking part and the connecting part of the connectors.
(c) Disconnect the skid control ECU connectors and the brake actuator connector.
(d) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
5. READ VALUE USING TECHSTREAM (WHEEL CYLINDER PRESSURE SENSOR)
(a) Reconnect the skid control ECU connectors and the brake actuator connector.
(b) Connect the pedal effort gauge.
(c) Install the hydro LSPV gauge and bleed air.
SST: 09709-29018
(d) Connect the Techstream to the DLC3.
(e) Turn the power switch on (IG).
(f) Select the Data List mode on the Techstream. Data List / Active Test
ABS / VSC / TRAC:
(g) Check the output value of the wheel cylinder pressure sensor at each hydraulic pressure level during the electronically controlled brake system control.
Standard voltage:
for front wheel cylinder pressure sensor
for rear wheel cylinder pressure sensor
NG -- REPLACE BRAKE ACTUATOR ASSEMBLY
OK -- Continue to next step.
6. CHECK BRAKE DISC
(a) Turn the power switch off.
(b) Disconnect the brake pedal stroke sensor connector.
(c) Perform a road test according to Freeze Frame Data or customer problem analysis. Check the brake line pressure vibration caused due to uneven wear of the disc according to brake pedal vibration.
OK:
Brake pedal does not vibrate during braking.
HINT:
- The brake pedal does not kick back due to wheel cylinder piston vibration during electronically controlled brake system control.
- If the brake pedal stroke sensor connector is disconnected, the fail safe function will prohibit electronically controlled brake system control.
- The Active Test does not prohibit electronically controlled brake system control when the vehicle is running, so disconnect the stroke sensor connector before continuing with inspection.
- Disc wear can be checked by measuring the disc thickness.
NG -- REPLACE BRAKE DISC
OK -- Continue to next step.
7. RECONFIRM DTC
(a) Reconnect the brake pedal stroke sensor connector.
(b) Clear the DTCs.
(c) Perform a road test under the same malfunction conditions recreated based on the Freeze Frame Data or customer problem analysis.
(d) Check if the same DTC is recorded.
Result:
B -- REPLACE BRAKE ACTUATOR ASSEMBLY
A -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)