P0571
DTC P0571 (4.8L, 5.3L, 6.0L, and 8.1L)
Circuit Description
The torque converter clutch (TCC) brake switch/cruise control release signal circuit is incorporated into the stop lamp switch. The TCC brake switch/cruise control release signal circuit portion of the stop lamp switch is a normally closed switch. The stop lamp switch signal circuit portion of the stop lamp switch is a normally open switch. When the brake pedal is released, the PCM detects a high voltage signal on the TCC brake switch/cruise control release signal circuit and a low signal voltage signal on the stop lamp switch signal circuit.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0571 Cruise Control Brake Switch Circuit
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
* When the brake pedal is released, the PCM detects a high voltage signal on the stop lamp switch signal circuit or when the PCM detects a low voltage signal on the TCC brake switch/cruise control release signal circuit.
* The above conditions are present for 2 seconds.
Action Taken When the DTC Sets
* The powertrain control module (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
* Refer to Exterior Lighting Systems Description and Operation in order to avoid a misdiagnosis.
* For an intermittent, Refer to Testing for Intermittent Conditions and Poor Connections. Component Tests and General Diagnostics
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