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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2008 🢒 Grand Prix 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 DTC C0241

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC C0241 00: Powertrain Control Module (PCM) Indicated Request Torque Malfunction

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

ECM/PCM Requested Torque Signal Circuit

C0241 00

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C0241 00

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Circuit Description

The electronic brake control module (EBCM) and the powertrain control module (PCM) or engine control module (ECM) simultaneously control the traction control. The EBCM sends a Requested Torque message via pulse width modulated (PWM) signal to the PCM or ECM to deliver. Normal values are between 10 and 90 percent duty cycle. The signal should be at least 90 percent when traction control is not active and at lower values during traction control activations. The PCM or ECM supplies the pull up voltage that the EBCM switches to ground to create the signal.

Conditions for Running the DTC

Ignition ON.

Conditions for Setting the DTC

The PCM/ECM 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/ECM 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 ABS/TCS/VSES/DRP for the duration of the ignition cycle.
    • A malfunction DTC will set.
    • The ABS indicator illuminates.
    • The Stability Off indicator illuminates.
    • The ABS remains functional.

Conditions for Clearing the DTC
    • The condition for the DTC is no longer present.
    • The EBCM clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Diagnostic Aids
    • Check both the EBCM, PCM, and ECM grounds, ensuring that each ground is clean and torqued to the proper specification.
    • Disconnecting the EBCM connector and turning ON ignition could cause other modules to set loss of communication DTCs (Uxxxx). Once the EBCM is reconnected, the EBCM may set DTC C0241.
    • This vehicle is equipped with a PCM or ECM which is electrically erasable programmable read only memory (EEPROM). When replacing the PCM or ECM, the replacement PCM or ECM must be programmed.

Reference Information

Schematic Reference

Antilock Brake System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

ABS Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Engine ON, verify the scan tool Torque Request signal parameter in the PCM or ECM data list.

⇒ The specified value should be less than 100 percent.

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector at the EBCM connector X1 terminal 13 or 14.
  2. Test for less than 1.0 ohm between the ground circuit connector X1 terminals 12 and 15 and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify that a test lamp illuminates between the B+ circuit of the EBCM supply voltage terminal connector X1 terminal 13 or 14 and ground.
    4. ⇒If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse (ABS MTR 40-amp) or (ABS SOL 25-amp) or (ABS 10-amp) in the fuse block underhood BEC is open, test all components connected to the B+ circuit and replace as necessary.
  4. Engine ON, measure the DC Hz for 121-134 Hz between the PCM or ECM requested torque signal circuit connector X3 terminal 21 (L26) or 25 (LS4) and a good ground.
    5. ⇒If the value is below the specified range, test the PCM or ECM requested torque signal circuit for an open/high resistance. If the circuit tests normal replace the PCM or ECM.
    ⇒If the value is above the specified range, test the PCM or ECM requested torque signal circuit for an short to voltage. If the circuit tests normal replace the PCM or ECM.
  5. Connect a DMM between the requested torque signal circuit connector X3 terminal 21 (L26) or 25 (LS4) of the PCM or ECM and a good ground.
  6. Test the requested torque signal circuit for 4-6 volts.
    7. ⇒If the voltage is below the specified range, test the requested torque circuit for a short to ground, or open/high resistance. If the circuit tests normal, replace the EBCM.
    ⇒If the voltage is above the specified range, test the requested torque circuit for a short to voltage. If the circuit tests normal, replace EBCM.
  7. If all circuits test normal, replace the EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for EBCM, PCM, or ECM replacement, setup, or programming