STEP 1. Check the stoplight switch.
STEP 2. Voltage measurement at ETACS-ECU connector (BKLP terminal).
(1) Measure by backprobing without disconnecting the ETACS-ECU connector and stoplight switch connector.
(2) Check the voltage between the ETACS-ECU connector (BKLP terminal) and ground.OK:
- When the brake pedal is released: Approximately 0 V - 5 V (pulse)
- When the brake pedal is depressed: Approximately system voltage
Is the check result normal?
Go to Step 5. Go to Step 3.
STEP 3. Check of short to power supply, short to ground, and open circuit in BKLP line between ETACS-ECU connector and stoplight switch connector.
STEP 4. Check of short to power supply, short to ground, and open circuit in STP line between ETACS-ECU connector and stoplight switch connector.
STEP 5. Using scan tool (M.U.T.-III), check data list.
(1) caution | To prevent damage to scan tool (M.U.T.-III), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-III). |
Connect scan tool (M.U.T.-III). Refer to "How to connect Scan Tool (M.U.T.-III)
."
(2) Temporarily replace the stoplight relay, and then depress the brake pedal. | Item No. | Item name | Normal condition | 290 | Stoplight switch | ON |
|
Item No. | Item name | Normal condition |
290 | Stoplight switch | ON |
OK: Normal condition is displayed.
Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ). Replace the ETACS-ECU.