P0571

Diagnostic Chart (Part 1 Of 2):

Diagnostic Chart (Part 2 Of 2):

Schematic:

CIRCUIT DESCRIPTION
The Torque Converter Clutch (TCC) normally closed cruise brake switch supplies a B+ signal on the brake switch input circuit to the Powertrain Control Module (PCM). The circuit is opened when the brakes are applied. The stoplamp/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 RUNNING THE DTC
The ignition is in the ON position.

CONDITIONS FOR SETTING THE DTC
^ The switches disagree for 10 consecutive minutes.

or

^ The TCC and the 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 will not illuminate the Malfunction Indicator Lamp (MIL).
^ The PCM records the operating conditions at the time the diagnostic fails. This information is stored in the Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC
^ A history DTC clears after 40 consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
^ The scan tool Clear Info function was used.

DIAGNOSTIC AIDS
Check the driving habits of the customer and/or unusual traffic conditions, for example, stop and go, and expressway traffic.

An open fuse on the stoplamp circuit may be caused by a short to ground on the feed or signal side of the stoplamp switch.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table:
4. This test checks the feed circuit.
6. This test simulates brake switch closed or brakes ON.