P0571

CIRCUIT DESCRIPTION
The normally closed TCC/Cruise brake switch supplies a B+ signal on the TCC/brake switch signal circuit to the PCM. The circuit is opened when the brakes are applied. The normally open stop lamp switch supplies a B+ signal on the stoplamp switch signal circuit to the PCM when the brake is applied.

CONDITIONS FOR RUNNING THE DTC
^ The stop lamp and TCC/cruise brake switch signal voltages are not what is anticipated by the PCM for 10 consecutive minutes.

or

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

CONDITIONS FOR SETTING THE DTC
^ The stop lamp and TCC/cruise brake switch signal voltages are not what is expected by the PCM for 10 consecutive minutes.

or

^ The TCC/cruise and stop lamp 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 clears after forty consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
^ The use of a scan tool.

DIAGNOSTIC AIDS
Check customer driving habits and/or unusual traffic conditions, i.e. stop and go, expressway traffic.

TEST

Steps 1-7:

Steps 8-10: