P1575
Circuit Description
This diagnostic test functions on the assumption that a brake application causes a sudden decrease in non-drive wheel speed.
The Extended Travel Brake Switch is a normally closed switch. When the Extended Travel Brake Switch is closed, the PCM senses ignition voltage on the Extended Travel Brake Switch signal circuit.
If the PCM senses a voltage on the Extended Travel Brake Switch signal circuit when the Extended Travel Brake Switch should be open, this DTC sets.
Conditions for Running the DTC
^ The engine speed is greater than 700 RPM.
^ The engine has been operating longer than 2 seconds.
^ The wheel speed must be greater than 30 MPH in order to enable the diagnostic. The diagnostic will disable when the wheel speed is below 10 MPH.
^ The vehicle speed is decreasing at a rate greater than 10.4 MPH over a one second period.
Conditions for Setting the DTC
^ The PCM detects voltage on the Extended Travel Brake Switch circuit when the Extended Travel Brake Switch should be open.
^ The above conditions present for 1.5 seconds.
Action Taken When the DTC Sets
^ The PCM stores the DTC information into memory when the diagnostic runs and fails.
^ The Malfunction Indicator Lamp (MIL) will not illuminate.
^ The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records.
Conditions for Clearing the MIL/DTC
^ A last test failed (current DTC) clears when the diagnostic runs and does not fail.
^ A History DTC clears after forty consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
^ Use a scan tool in order to clear the MIL/DTC.
Diagnostic Aids
Important:
^ Remove any debris from the PCM/TAC module connector surfaces before servicing the PCM/TAC module. Inspect the PCM/TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM/TAC modules.
^ For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter Kit J 35616-A. Using this kit prevents damage to the harness/component terminals.
^ Test drive the vehicle if you cannot find a problem with the switch or the circuit. An intermittent condition may be duplicated on a test drive.
^ This DTC does not set for an open circuit. If the PCM senses the Extended Travel Brake switch is Applied when the brake pedal is actually released a driveability concern may result.
^ For an intermittent condition, refer to Symptoms. Symptom Related Diagnostic Procedures
Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. An Extended Travel Brake switch signal that indicates Applied when the pedal is actually released may cause a driveability concern.
4. An Extended Travel Brake switch that is not properly adjusted may cause this DTC to set.
6. This step tests for an Extended Travel Brake Switch circuit for being shorted to B+.