P0504
DTC P0504 Brake Switch "A" / "B" CorrelationDESCRIPTION
DTC Detection Condition:
In addition to turning on the stop lights, the stop light switch signals are used for a variety of engine, transmission and suspension functions. The stop light switch is designed with 2 complementary signal outputs, STP and ST1-. The ECM analyzes these signal outputs to detect malfunctions in the stop light switch.
HINT: Normal condition is as shown in the table.
Wiring Diagram:
INSPECTION PROCEDURE
HINT: Read freeze frame data using the intelligent tester or the OBD II scan tool. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
Step 1-3:
Step 3(Continued)-4:
Intelligent tester
Step 1:
Step 2-3:
Step 4:
OBD II scan tool (excluding Intelligent Tester)