Engine Controls

P1805 BRAKE SWITCH





Description
Brake switch signal is applied to the ECM and hybrid vehicle control ECU through the stop lamp switch when the brake pedal is depressed. This signal is used mainly to decrease the engine speed when the vehicle is driving.




DTC Logic

DTC DETECTION LOGIC






DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Fully depress the brake pedal for at least 5 seconds.
3. Erase the DTC with CONSULT-III.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES - Go to SEE Diagnosis Procedure.
NO - INSPECTION END




Diagnosis Procedure
1.CHECK STOP LAMP SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Check the stop lamp when depressing and releasing the brake pedal.





Is 1st trip DTC detected?
YES - GO TO 4.
NO - GO TO 2.
2.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 4.
NO - GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
- Fuse block (J/B) connector E6
- 10A fuse (No. 7)
- Harness for open or short between stop lamp switch and battery
- Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK STOP LAMP RELAY-1 GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp relay-1 harness connector.





3. Check the continuity between stop lamp relay-1 harness connector and and ground.





Is the inspection result normal?
YES - GO TO 5.
NO - Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT
1. Connect stop lamp switch harness connector.
2. Turn ignition switch ON.





3. Check the voltage between stop lamp relay-1 harness connector and ground.





Is the inspection result normal?
YES - GO TO 7.
NO - GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
- Joint connector E-14 E96
- Harness for open or short between stop lamp switch and stop lamp relay-1
Is the inspection result normal?
YES - GO TO 9.
NO - Repair open circuit or short to ground or short to power in harness or connectors.
7.CHECK STOP LAMP RELAY-1 POWER SUPPLY CIRCUIT





1. Check the voltage between stop lamp relay-1 harness connector and ground.





Is the inspection result normal?
YES - GO TO 8.
NO - Repair open circuit or short to ground or short to power in harness or connectors.
8.CHECK STOP LAMP RELAY-1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect stop lamp relay-1 harness connector.
3. Check the continuity between stop lamp relay-1 harness connector and ECM harness connector.





4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES - GO TO 10.
NO - Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK STOP LAMP SWITCH
SEE Component Inspection (Stop Lamp Switch).
Is the inspection result normal?
YES - GO TO 11.
NO - Replace stop lamp switch. Removal And Installation.
10.CHECK STOP LAMP RELAY-1
SEE Component Inspection (Stop Lamp Relay-1).
Is the inspection result normal?
YES - GO TO 11.
NO - Replace stop lamp relay-1.For the relay number, [1][2]Electrical Diagrams. For the relay arrangement, Harness Locations.
11.CHECK INTERMITTENT INCIDENT
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. Inspection and Adjustment.





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. Removal And Installation.




Component Inspection (Stop Lamp Relay-1)
1. STOP LAMP RELAY-1
1. Turn ignition switch OFF.
2. Remove stop lamp relay-1. For the relay number, [1][2]Electrical Diagrams. For the relay arrangement, Harness Locations.





3. Check continuity between stop lamp relay-1 terminals under the following conditions.





Is the inspection result normal?
YES - INSPECTION END
NO - Replace stop lamp relay-1. For the relay number, [1][2]Electrical Diagrams. For the relay arrangement, Harness Locations.