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DTC B1136: Stop light switch
 
 
cautionWhen replacing the ECU, always check that the communication circuit is normal.
 
 
TECHNICAL DESCRIPTION (COMMENT)
When the stop light switch status is different from the brake switch information received from ETACS-ECU via CAN, OSS-ECU stores DTC B1136, and displays the power supply system error warning the combination meter, and flashes the indicator of engine switch in orange.
 
 
DTC SET CONDITION
Check Conditions
  • After OSS-ECU activation
Judgment Criterion
  • When the following conditions are met:
    1. When the stop light switch is OFF and the brake switch status is ON, 1.5 seconds or more have elapsed
    2. When the stop light switch is ON and the brake switch status is OFF, 1.5 seconds or more have elapsed
 
 
TROUBLESHOOTING HINTS
  • Damaged wiring harness or connector (short to ground or open circuit between stop light switch and OSS-ECU or between stop light switch and ETACS-ECU)
  • ETACS-ECU malfunction
  • Malfunction of OSS-ECU
 
 
DIAGNOSIS
STEP 1. Check of short to ground and open circuit in STP1 line between stop light switch connector and OSS-ECU connector
Is the check result normal?
Go to Step 2.
Repair the connector(s) or wiring harness.
 
STEP 2. Check of short to ground and open circuit in BKLP line between stop light switch connector and ETACS-ECU connector
Is the check result normal?
Go to Step 3.
Repair the connector(s) or wiring harness.
 
STEP 3. Using scan tool (M.U.T.-III), check other system data list.
(1)
cautionTo prevent damage to scan tool (M.U.T.-III), always turn the power supply mode of the engine switch to the 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) After performing the forced power supply output (refer to forced power supply output procedure ) "IG-ON".
(3) Check the ETACS-ECU data list.
  • Item No.108: Stop light switch (Refer to GROUP 54A - ETACS, Service Data Reference Table .)
(4) Turn the power supply mode of the engine switch to OFF.
Is the check result normal?
Go to Step 4.
Diagnose the ETACS-ECU. (Refer to GROUP 54A - ETACS, Trouble Symptom Chart for Input Signal .)
 
STEP 4. Using scan tool (M.U.T.-III), check data list.
(1)
cautionTo prevent damage to scan tool (M.U.T.-III), always turn the power supply mode of the engine switch to the OFF position before connecting or disconnecting scan tool (M.U.T.-III).
Connect scan tool (M.U.T.-III). Refer to "How to connect the Scan Tool (M.U.T.-III) ."
(2) Turn the power supply mode of the engine switch to OFF.
(3) Check the OSS-ECU data list.
  • Operate the brake pedal.
 
Item No.Check itemOperation stateDisplay
3Stop light switchBrake pedal is depressedON
Brake pedal releasedOFF
OK: Operation state and data list display agree with each other.
Is the check result normal?
Go to Step 5.
Replace the OSS-ECU and register the VIN (Refer to ).
 
STEP 5. Recheck for diagnostic trouble code.
(1) Erase the DTC.
(2) Turn the power supply mode of the engine switch from OFF to ON.
(3) Check if DTC is stored.
(4) Turn the power supply mode of the engine switch from ON to OFF.
Is the DTC stored?
Replace the OSS-ECU and register the VIN (Refer to ).
Intermittent malfunction is suspected (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).