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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 1999 🢒 Firebird 🢒 Brakes 🢒 Antilock Brake System 🢒 DTC C0241 PCM Indicated Requested Torque Malf

Object Number: 314216 Size: SF
ABS Components
3.8L With Traction Control

Circuit Description

Traction Control is simultaneously controlled by the EBTCM and the ECM. The EBTCM sends a requested torque message via a Pulse Width Modulated (PWM) signal to the ECM requesting a desired engine torque level for proper Traction Control system operation. The PCM supplies the pull up voltage.

Conditions for Setting the DTC
    • If a defective requested torque signal is detected by the PCM, a message is broadcasted back to the EBTCM via class 2.
    • DTC C0241 can be set anytime when ignition voltage is present and the EBTCM detects the first class 2 message of a defective requested torque signal from the PCM.

Action Taken When the DTC Sets
    • A malfunction DTC is stored.
    • The TCS is disabled.
    • The TRAC OFF indicator is turned on. The ABS remains functional.

Conditions for Clearing the DTC
    • Condition for DTC is no longer present and scan tool clear DTC function is used.
    • 100 ignition cycles have passed with no DTC(s) detected.

Diagnostic Aids
    • It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction.
    • If an intermittent malfunction exists, refer to General Electrical Diagnosis in Wiring Systems.
    • Possible causes for DTC C0241 to set:
       - Open in the circuit 463.
       - Circuit 463 shorted to ground or voltage.
       - Communication problem.
       - Circuit 463 has a wiring problem, terminal corrosion, or poor connections.
       - PCM not receiving information from the EBTCM.

Test Description

The numbers below refer to step numbers on the diagnostic table.

  1. Step 4 checks for the proper requested torque value received at the PCM. This value is in percent of torque.

    2.

  2. Step 5 checks for the proper requested torque value sent from the EBTCM. This value is in newton meters of torque.

    3.

  3. Step 7 checks for the presence of a pull-up voltage from the PCM.

DTC C0241 PCM Indicated Requested Torque Malfunction

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check - ABS

2

Check that ground, G101 and G106 is clean, tight and free of damage. Refer to Power and Grounding Components in Wiring Systems.

Were any loose, damaged, or corroded grounds found?

--

Go to Step 3

Go to Step 4

3

Repair ground as necessary. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

4

  1. Turn the ignition switch to the OFF position.
  2. Install the scan tool.
  3. Start the engine.
  4. Use the scan tool to select Engine 2 Data Display in Powertrain.
  5. Using the scan tool, observe the Traction Control Desired Torque.

Is the desired torque within the range specified in the value(s) column?

80-95 %

Go to Step 5

Go to Step 7

5

  1. Turn the engine off.
  2. Turn the ignition switch to the run position, engine off.
  3. Using the scan tool, select ABS/TCS Data Display.
  4. Observe the EBTCM to PCM Requested Torque.

Is the requested torque within the range specified in the value(s) column?

0 N·m

Go to Step 13

Go to Step 6

6

Replace the EBTCM. Refer to Electronic Brake Control Module Replacement .

Is the replacement complete?

--

Go to Diagnostic System Check - ABS

--

7

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the EBTCM connector.
  3. Install J 39700 Universal Pinout Box using the J 39700-530 cable adapter to the EBTCM harness connector.
  4. Turn the ignition switch to the RUN position, engine off.
  5. Using J 39200 DMM, measure the voltage between terminals 27 and 15 of J 39700 .

Is the voltage within the range specified in the value(s) column?

4.5-5.5 V

Go to Step 6

Go to Step 10

8
  1. Turn the ignition switch to the OFF position.
  2. Disconnect the PCM connector C1.
  3. Turn the ignition switch to the RUN position, engine off.
  4. Using J 39200 DMM, measure the voltage between terminals 27 and 15 of J 39700 .

Is the voltage greater than the specified value?

1 V

Go to Step 9

Go to Step 10

9

Repair CKT 463 for a short to voltage. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

10
  1. Turn the ignition switch to the OFF position.
  2. Using J 39200 DMM, measure the resistance between J 39700 terminals 27 and 15.

Is the resistance within the range specified in the value(s) column?

OL (infinite)

Go to Step 12

Go to Step 11

11

Repair CKT 463 for a short to ground. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

12
  1. Turn the ignition switch to the OFF position.
  2. Using J 39200 DMM, measure the resistance between terminal 27 of J 39700 and the PCM connector C2 terminal 71.

Is the resistance within the range specified in the value(s) column?

0-2 ohms

Go to Step 13

Go to Step 14

13

Suspect PCM. Refer to Powertrain OBD System Check in Engine Controls.

Is the Repair complete?

--

Go to Diagnostic System Check - ABS

--

14

Repair CKT 463 for an open. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--