ELECTRIC PARKING BRAKE AUTOMATIC RELEASE FUNCTION DURING ACCELERATION DOES NOT OPERATE [ELECTRIC PARKING BRAKE]


id040328250500


Outline

Description
The electric parking brake automatic release function during acceleration does not operate.
Possible cause
•  Electronically controlled brake unit malfunction
•  Front door latch and lock actuator (driver’s side) connector or terminal malfunction
•  Front door latch and lock actuator (driver’s side) malfunction
•  Door-electrical supply unit (driver’s side) connector or terminal malfunction
•  Short to ground in front door latch switch (driver’s side) signal circuit
•  Door-electrical supply unit (driver’s side) malfunction
•  Connector C-70 connector or terminal malfunction
•  Driver’s side front buckle switch malfunction
•  Dash-electrical supply unit connector or terminal malfunction
•  Short to ground in driver’s side front buckle switch signal circuit
•  Dash-electrical supply unit malfunction


Diagnostic Procedure

Step

Inspection

Results

Action

1
VERIFY SYSTEM DTCs
•  Switch the main power OFF.
•  Switch the main power ON (READY off or on) and wait for 10 s or more.
•  Perform a Quick Check using the M-MDS.
•  Are any DTCs displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
No
Go to the next step.
2
VERIFY ELECTRIC PARKING BRAKE WARNING LIGHT ON CONDITION
•  Verify if the electric parking brake warning light is turned on.
•  Is the electric parking brake warning light turned on?
Yes
Perform an inspection referring to the [ELECTRIC PARKING BRAKE WARNING LIGHT TURNED ON] item.
No
Go to the next step.
3
DETERMINE MALFUNCTIONING LOCATION BY PERFORMING PID/DATA MONITOR INSPECTION
•  Using the M-MDS, display the following PIDs for the door-electrical supply unit (driver’s side).
―  DOOR_SW_D (front door (driver’s side) open/closed condition)
•  Using the M-MDS, display the following PIDs for the dash-electrical supply unit.
―  S_BELT_STAT (driver’s seat belt fastened condition)
•  Does the PID value switch correctly in conjunction with the opening/closing of the front door (driver’s side) or with the driver’s seat belt fastened?
Yes
Replace the electronically controlled brake unit and perform the repair completion verification.
No
Not in conjunction with front door (driver’s side) open/close:
•  Go to the next step.
Not in conjunction with driver's seat belt fastened:
•  Go to Step 8.
4
INSPECT FRONT DOOR LATCH AND LOCK ACTUATOR (DRIVER’S SIDE) CONNECTOR FOR MALFUNCTION
•  Inspect the applicable connector and terminal.
•  Is the connector normal?
Yes
Go to the next step.
No
Repair or replace the malfunctioning location and perform the repair completion verification.
5
INSPECT FRONT DOOR LATCH SWITCH (DRIVER’S SIDE) FOR MALFUNCTION
•  Inspect the applicable part.
•  Is the front door latch switch (driver’s side) normal?
Yes
Go to the next step.
No
Replace the front door latch and lock actuator (driver’s side) and perform the repair completion verification.
6
INSPECT DOOR-ELECTRICAL SUPPLY UNIT (DRIVER’S SIDE) CONNECTOR FOR MALFUNCTION
•  Inspect the applicable connector and terminal.
•  Is the connector normal?
Yes
Go to the next step.
No
Repair or replace the malfunctioning location and perform the repair completion verification.
7
INSPECT FRONT DOOR LATCH SWITCH (DRIVER’S SIDE) SIGNAL CIRCUIT FOR SHORT TO GROUND
•  Inspect the applicable circuit for a short to ground.
•  Is the circuit normal?
Yes
Replace the door-electrical supply unit (driver’s side) and perform the repair completion verification.
No
Repair or replace the malfunctioning location and perform the repair completion verification.
8
INSPECT CONNECTOR C-70 CONNECTOR FOR MALFUNCTION
•  Inspect the applicable connector and terminal.
•  Is the connector normal?
Yes
Go to the next step.
No
Repair or replace the malfunctioning location and perform the repair completion verification.
9
INSPECT DRIVER’S SIDE FRONT BUCKLE SWITCH FOR MALFUNCTION
•  Inspect the applicable part.
•  Is the driver’s side front buckle switch normal?
Yes
Go to the next step.
No
Replace the driver’s side front buckle and perform the repair completion verification.
10
INSPECT DASH-ELECTRICAL SUPPLY UNIT CONNECTOR FOR MALFUNCTION
•  Inspect the applicable connector and terminal.
•  Is the connector normal?
Yes
Go to the next step.
No
Repair or replace the malfunctioning location and perform the repair completion verification.
11
INSPECT DRIVER’S SIDE FRONT BUCKLE SWITCH SIGNAL CIRCUIT FOR SHORT TO GROUND
•  Inspect the applicable circuit for a short to ground.
•  Is the circuit normal?
Yes
Replace the dash-electrical supply unit and perform the repair completion verification.
No
Repair or replace the malfunctioning location and perform the repair completion verification.
Repair completion verification
VERIFY IF MALFUNCTION CAUSE IS CORRECTED
•  Install/connect the part removed/disconnected during the troubleshooting procedure.
•  Has the malfunction symptom been eliminated?
Yes
Complete the symptom troubleshooting.
Explain repair contents to customer.
No
Refer to the CAN (controller area network) malfunction diagnosis flow to inspect for a CAN communication error.
If the CAN communication is normal, perform the diagnosis from Step 1.