DTC P0504 Brake Switch "A" / "B" Correlation: Description
WARNING: This page is about a different car, the 2007 Toyota Land Cruiser. However, it is still accessible from the selected car via links, so may be relevant.
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 below. The signals can be read using the intelligent tester.
BRAKE PEDAL OPERATION
| Signal | Brake Pedal Released | In Transition | Brake Pedal Depressed |
|---|---|---|---|
| STP | OFF | ON | ON |
| ST1- | ON | ON | OFF |
DTC TROUBLE DETECTION CONDITION
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| P0504 | Conditions (a), (b) and (c) continue for 0.5 sec or more:
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