Inspection Procedure 8: The electric parking brake switch indicator light does not come on or flash normally.
OPERATION
The electric parking brake switch indicator light illuminates when the electric parking brake is activated.
The electric parking brake switch indicator light blinks when the overheat protection mode for electric motor or the maintenance mode is activated.
COMMENTS ON TROUBLE SYMPTOM
When the electric parking brake switch indicator light illuminates or blinks normally, the electric parking brake switch, the electric parking brake ECU or its associated wire(s) or connector(s) may be defective.
TROUBLESHOOTING HINTS
Malfunction of the electric parking brake switch (indicator light)
Malfunction of the electric parking brake ECU
Damaged wiring harness or connector
DIAGNOSIS
Required Special Tools:
MB992006: Extra Fine Probe
STEP 1. Check the electric parking brake switch (indicator light).
Check the electric parking brake switch (indicator light) (Refer to ).
Is the check result normal?
Go to Step 2
Replace the electric parking brake switch (Refer to ).
STEP 2. Measure the voltage at the electric parking brake switch connector.
(1) Disconnect the electric parking brake switch connector and measure at the wiring harness side.
(2) Measure the voltage between the terminal No.5 and ground.
OK: The voltage should measure approximately 12 volts (battery positive voltage).
Is the check result normal?
Go to Step 3
The power supply circuit may be open. Repair the wiring harness wires or connectors between the electric parking brake switch connector and the fusible link.
STEP 3. Measure the resistance at the electric parking brake ECU connector and the electric parking brake switch connector.
(1) Disconnect the connector and measure at the wiring harness side.
(2) Measure the resistance between the electric parking brake ECU connector PIND terminal and the electric parking brake switch connector terminal No.6.
OK: The resistance should be 2 ohms or less
(3) Measure the resistance between the electric parking brake ECU connector PIND terminal and ground.
OK: No continuity.
Is the check result normal?
Go to Step 4
The signal circuit may be open or short to ground. Repair the wiring harness wires or connectors between the electric parking brake switch and the electric parking brake ECU.
STEP 4. Retest the system.
Is the check result normal?
The trouble can be an intermittent malfunction (GROUP 00 - How to use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Replace the electric parking brake ECU (Refer to ).