P1805-902

P1805-902





Description
Brake switch signal is applied to the hybrid vehicle control ECU through the stop lamp switch when the brake pedal is depressed. This signal is used mainly for the ASCD function and regenerative brake control.




DTC Logic

DTC DETECTION LOGIC









Component Function Check
1.CHECK FOR STOP LAMP SWITCH FUNCTION
With CONSULT-III
1. Turn ignition switch ON.
2. Select "BRAKE SWITCH" in "DATA MONITOR" mode with CONSULT-III.
3. Check "BRAKE SWITCH" indication under the following conditions.






With GST
1. Turn ignition switch ON.
2. Check the voltage between hybrid vehicle control ECU harness connector and ground.






Is the inspection result normal?
YES - INSPECTION END
NO - Go to "Diagnosis Procedure".




Diagnosis Procedure
1.PRECONDITIONING
- Before inspecting the high-voltage system or disconnecting the low voltage connector of the inverter with converter assembly, take safety precautions such as wearing insulated gloves and removing the service plug grip to prevent electrical shocks. After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.
- After disconnecting the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals.
- Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.
- GO TO 2.
2.CHECK STOP LAMP SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Check the stop lamp when depressing and releasing the brake pedal.






Is the inspection result normal?
YES - GO TO 5.
NO - GO TO 3.
3.CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.






3. Check the voltage between stop lamp switch harness connector and ground.






Is the inspection result normal?
YES - GO TO 5.
NO - GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
- Junction block connector E6
- 10A fuse (No. 7)
- Harness for open or short between stop lamp switch and battery
- Repair open circuit or short to ground in harness or connectors.
5.CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect hybrid vehicle control ECU harness connector.
2. Check the continuity between hybrid vehicle control ECU harness connector and stop lamp switch harness connector.






3. Also check harness for short to ground.
Is the inspection result normal?
YES - GO TO 7.
NG - GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
- Joint connector E-4
- Harness for open or short between hybrid vehicle control ECU and stop lamp switch
- Repair open circuit or short to ground in harness or connectors.
7.CHECK STOP LAMP SWITCH
Refer to "Component Inspection (Stop Lamp Switch)".
Is the inspection result normal?
YES - GO TO 8.
NO - Replace stop lamp switch.
8.CHECK INTERMITTENT INCIDENT
Refer to Intermittent Incident.
- INSPECTION END




Component Inspection (Stop Lamp Switch)
1.CHECK STOP LAMP SWITCH-I
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.






3. Check the continuity between stop lamp switch terminals under the following conditions.






Is the inspection result normal?
YES - INSPECTION END
NO - GO TO 2.
2.CHECK STOP LAMP SWITCH-II
1. Adjust stop lamp switch installation. Refer to Procedures.






2. Check the continuity between stop lamp switch terminals under the following conditions.






Is the inspection result normal?
YES - INSPECTION END
NO - Replace stop lamp switch.