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P0504

DTC P0504 Brake Switch "A"/"B" Correlation

DESCRIPTION




DTC Detection Condition:




In addition to turning on the stop light, the stop light switch signals are used for a variety of engine, transmission, and suspension functions as well as being an input for diagnostic checks. It is important that the switch operates properly, therefore this 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:






Step 1-3:




Step 3(Continued)-4:




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.