C0241

DTC C0241 or P1571





Test 1-4





Test 5-13

Circuit Description
The EBCM and the PCM simultaneously control the traction control. The EBCM sends a Requested Torque message via a pulse width modulated (PWM) signal to the PCM. The duty cycle of the signal is used to determine how much engine torque the EBCM is requesting the PCM to deliver. Normal values are between 10 and 90 percent duty cycle. The signal should be at 90 percent when traction control is not active and at lower values during traction control activations. The PCM supplies the pull up voltage that the EBCM switches to ground to create the signal.

Conditions for Running the DTC
The ignition is ON.

Conditions for Setting the DTC
The PCM diagnoses the requested torque PWM signal circuit and sends a class 2 serial data message to the EBCM indicating a fault is present. A fault exists in the circuit if the PCM detects one of the following conditions:
^ The requested torque PWM signal is less than 5 percent duty cycle or greater than 95 percent duty cycle.
^ The requested torque PWM signal is not present for 10 seconds.

Action Taken When the DTC Sets
If equipped, the following actions occur:
^ The EBCM disables the TCS/VSES for the duration of the ignition cycle.
^ A malfunction DTC will set.
^ The TRAC OFF indicator turns ON.
^ The PCS indicator turns ON.
^ The ABS remains functional.

Conditions for Clearing the DTC
^ The condition for the DTC is no longer present (the DTC is not current) and you used the scan tool Clear DTC function.
^ The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
3. Use the scan tool in order to determine if the requested torque signal has a valid duty cycle.
4. Measure the requested torque signal in order to determine if the signal has a valid duty cycle.
5. Measure the requested torque signal in order to determine if the signal has a valid frequency.
11. This vehicle is equipped with a PCM, which uses an Electrically Erasable Programmable Read Only Memory (EEPROM). When replacing the PCM, the replacement PCM must be programmed.