P1571

Schematic:

CIRCUIT DESCRIPTION

The traction control system uses the antilock brake system in conjunction with the Powertrain Control Module (PCM) fuel and ignition controls to limit drive wheel slippage during acceleration. The PCM controlled portion of the traction control system reduces engine torque by any or all of the following methods:
^ Retarding the spark timing
^ Altering the air/fuel ratio
^ Altering the boost PWM
^ Shutting OFF up to 3 injectors

To determine the amount of torque reduction required, the PCM monitors the TCS Desired Torque PWM signal from the Electronic Brake And Traction Control Module (EBTCM). The PCM also provides a TCS delivered torque PWM informing the EBTCM of how much torque is being produced by the engine. The Desired Torque display on the scan tool indicates the amount of engine torque requested by the EBTCM. With the traction control inactive, the Desired Torque should vary between 99 and 100 percent. The Desired Torque display on the scan tool is not the PWM duty cycle.

CONDITIONS FOR RUNNING THE DTC
The traction control is active.

CONDITIONS FOR SETTING THE DTC
^ The desired torque signal PWM duty cycle is less than 5 percent or more than 95 percent.
^ The conditions exist for up to 10 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM will not illuminate the Malfunction Indicator Lamp (MIL).
^ The PCM will store conditions which were present when the DTC set as Failure Records data only. This information will not be stored as Freeze Frame data.

Steps 1 - 7:

Steps 8 - 11:

CONDITIONS FOR CLEARING THE MIL/DTC
^ A History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
^ The DTC can be cleared by using a scan tool.

DIAGNOSTIC AIDS
An intermittent may be caused by a faulty connection, rubbed through wire insulation, or a wire broken inside the insulation. Check for the following conditions:
^ A faulty connection or a damaged harness- Inspect the PCM harness for an open or a short to ground in the desired torque PWM circuit, improper mating, broken locks, improperly formed or damaged terminals, faulty terminal to wire connections, and damaged harnesses.
^ Using a scan tool, observe the Desired Torque display while moving the related connectors and wiring harness. If the failure is induced, the displayed value will change. This may help to isolate the location of the malfunction.

Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.