DTC P0504
Precautions: General safety (00)
DTC Detecting Condition and Trouble Area
| DTC detecting condition | Trouble area |
|---|---|
|
P0504: Brake Switch “A” / “B” Correlation Brake light switch signal does not correlate with brake switch signal. (3 D/C detection logic but MIL does not light up) |
•Brake light switch / brake switch and/or its circuit
•ECM |
Circuit Diagram
| [A]: | ECM connector (View: [a]) | B2: | Brake light switch signal circuit | 4. | “CRUISE” fuse |
| A1: | Brake switch power supply circuit | 1. | Brake light switch / brake switch | 5. | “STOP” fuse |
| A2: | Brake light switch power supply circuit | 2. | Brake light | 6. | To other control modules |
| B1: | Brake switch signal circuit | 3. | ECM |
DTC Confirmation Procedure
WARNING:
If you do not select a suitable route and take proper precautions when performing a road test, an accident can occur.
•Select a level road with no traffic to minimize the risk of accident.
•Perform the test extremely carefully.
•Perform the road test with 2 persons, a driver and a tester.
•Perform the test extremely carefully.
•Perform the road test with 2 persons, a driver and a tester.
1)Warm up engine to normal operating temperature.
2)Run engine at idle speed.
3)Depress and release brake pedal 10 times.
DTC Troubleshooting
| Step | Action | Yes | No |
|---|---|---|---|
| 1 |
Was “Engine and Emission Control System Check” performed?
|
Go to Step 2.
|
|
| 2 |
Brake light switch / brake switch power supply circuit check
1)With ignition “OFF”, disconnect brake light switch / brake switch connector.
2)Check for proper terminal connection to brake light switch / brake switch connector.
3)If connection is OK, set ignition “ON”.
4)Check that voltage between each of “A1” and “A2” circuits and ground is battery voltage.
Is check result OK?
|
Go to Step 3.
|
Repair or replace defective wire harness.
|
| 3 |
Brake light switch / brake switch signal circuit check
1)With ignition “OFF”, disconnect “C01” and “E01” connectors from ECM.
2)Check for proper terminal connection to “C01” and “E01” connectors.
3)If connections are OK, check the following points.
•Resistance of “B1” and “B2” circuits: less than 1 Ω
•Resistance between each of “B1” and “B2” circuits and ground: infinity •Resistance between “B1” circuit terminal and other terminal at brake light switch / brake switch connector: infinity •Resistance between “B2” circuit terminal and other terminal at brake light switch / brake switch connector: infinity •Voltage of “B1” and “B2” circuits: approx. 0 V (When ignition is “ON”) Is check result OK?
|
Go to Step 4.
|
Repair or replace defective wire harness.
|
| 4 |
Brake light switch / brake switch check
1)Check brake light switch / brake switch.
Is check result OK?
|
Replace ECM and recheck DTC.
|
Replace brake light switch / brake switch.
|