P0571

CIRCUIT DESCRIPTION
The TCC Brake switch contacts are normally closed contacts within the stoplamp switch. When the TCC Brake switch contacts are closed, the PCM senses ignition voltage on the TCC Brake switch signal circuit.

If the PCM senses a voltage on the TCC Brake switch signal circuit when the TCC Brake switch contacts should be open, this DTC sets.

CONDITIONS FOR RUNNING THE DTC
^ The engine speed is greater than 700 RPM.
^ The engine operates for greater than 2 seconds.
^ The wheel speed is greater than 48 km/h (30 mph) in order to enable the diagnostic. The diagnostic disables when the wheel speed is below 16 km/h (10 mph).

CONDITIONS FOR SETTING THE DTC
^ The PCM detects voltage on the TCC Brake switch signal circuit when the TCC Brake switch contacts should be open.
^ All above conditions are 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 DTC
^ A last test failed, or current DTC, clears when the diagnostic runs and does not fail.
^ A history DTC will clear after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
^ Use a scan tool in order to clear the DTC.

DIAGNOSTIC AIDS

IMPORTANT:
^ Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM.
^ For any test that requires probing the PCM or a component harness connector, use a connector test adapter. Using a connector test adapter prevents damage to the harness/component terminals. Refer to Using Connector Test Adapters in Diagnostic Aids.
^ Test drive the vehicle if a switch or circuit condition cannot be located. An intermittent condition may be duplicated during a test drive.
^ For an intermittent, refer to Testing for Intermittent and Poor Connections in Diagnostic Aids.

TEST DESCRIPTION

Steps 1-10:

The numbers below refer to the step numbers on the diagnostic table.
2. This step determines if the fault is present.