P0571

Diagnostic Chart:

Wiring Diagram:

Circuit Description

The Torque Converter Clutch (TCC) normally closed brake switch supplies a B+ signal on the Brake Switch Input circuit to the PCM. The circuit is opened when the brakes are applied. The stop lamp/cruise control normally open brake switch supplies a B+ signal on the Stoplamp Switch Input circuit to the PCM when the brake is applied.

Conditions for Selling the DTC

^ Brake switches disagree for 10 consecutive minutes.

or

^ TCC and cruise control brake switches are not toggling open and closed, during 6 brake applications on the same ignition cycle.

Action Taken When the DTC Sets

^ The PCM disallows all cruise control inputs.

^ TCC shift schedules may be affected.

^ The PCM will not illuminate the Malfunction Indicator Lamp (MIL).

^ The PCM records the operating conditions at the time the diagnostic fails. This information stores in the Failure Records.

Conditions for Clearing the MIL/DTC

^ A History DTC will clear when forty consecutive warm-up cycles that the diagnostic does not fail (coolant temperature has risen 5°C (40°F) from start up coolant temperature and engine coolant temperature exceeds 71°C (160°F) that same ignition cycle.

^ Use of a Scan tool

Diagnostic Aids

Refer to PCM Intermittent Diagnostic Trouble Codes or Performance. Check customer driving habits and/or unusual traffic conditions (i.e. stop and go, expressway traffic).

Test Description

Number(s) below refer to the step number(s) on the Diagnostic Table.

2. This test simulates brake switch closed or brakes OFF.

3. This test checks the feed circuit.