GM Service Manual Online
For 1990-2009 cars only

Object Number: 247758  Size: MF
ABS Components
Antilock Brake System Schematics
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The traction control system uses the antilock brake system in conjunction with the 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 performing one or both of the following actions:

    • Retarding the spark timing and alternating the air/fuel ratio
    • Shutting off up to three injectors

The EBCM/EBTCM sends a torque request to the PCM via a Pulse Width Modulated (PWM) signal requesting the desired torque level for proper traction control system operation (CKT 463). The PCM then provides a delivered torque PWM signal (CKT 464) informing the EBCM/EBTCM how much actual torque the engine produces.

Conditions for Setting the DTC

DTC C1324 will set when one of the following conditions occurs:

    • A malfunction exists in the delivered torque circuit (CKT 463).
    • The signal is out of range.

Action Taken When the DTC Sets

    • A malfunction DTC stores.
    • The ETS/TCS disables.
    • The amber TCS indicator turns on.

Conditions for Clearing the DTC

    • The condition responsible for setting the DTC no longer exists and the Scan Tool Clear DTCs function is used.
    • 100 drive cycles pass with no DTC(s) detected.

Diagnostic Aids

The following conditions may cause an intermittent malfunction:

    • A poor connection
    • Rubbed-through wire insulation
    • A broken wire inside the insulation

Use the enhanced diagnostic function of the Scan Tool in order to measure the frequency of the malfunction. Refer to the scan tool manual for the procedure.

Thoroughly inspect any circuitry that may cause the intermittent complaint for the following conditions:

    • Backed out terminals
    • Improper mating
    • Broken locks
    • Improperly formed or damaged terminals
    • Poor terminal-to-wiring connections
    • Physical damage to the wiring harness

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check

2

Inspect the following grounds in order to verify that each ground is clean and torqued to the proper specifications:

    • G113
    • G201
        Refer to Ground Distribution and Component Location Views, in Electrical Diagnosis for ground specifications and locations.

Are any of the grounds loose, damaged, or corroded?

--

Go to Step 18

Go to Step 3

3

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the PCM connector C1.
  3. Turn the ignition switch to the RUN position.
  4. Do not start the engine.

  5. Use the J 39200 in order to measure the voltage between the 8-way EBCM/EBTCM harness connector C3 terminal B and ground.

Is the voltage equal to or greater than the specified voltage?

4.5-5.5 V

Go to Step 6

Go to Step 4

4

Use the J 39200 in order to measure the voltage between the 8-way EBCM/EBTCM harness connector terminal B and ground.

Is the voltage equal to or greater than the specified voltage?

10.0 V

Go to Step 5

Go to Step 7

5

  1. Turn the ignition switch to the OFF position.
  2. Disconnect PCM connector C1.
  3. Turn the ignition switch to the RUN position.
  4. Do not start the engine.

  5. Use the J 39200 in order to measure the voltage between the 8-way EBCM/EBTCM harness connector C3 terminal B and ground.

Is the voltage within the specified voltage?

0.0-2.0 V

Go to Step 16

Go to Step 12

6

  1. Turn the ignition switch to the OFF position.
  2. Inspect the following components for signs of damage:
  3. • CKT 463
    • The 8-way EBCM/EBTCM harness connector C3 terminal B
    • The PCM harness connector C1 terminal 14
  4. Inspect the remaining terminals of the 8-way EBCM/EBTCM harness connector C1 for the following conditions:
  5. • Damage
    • Poor terminal contact
    • Terminal corrosion

Are poor terminal contact, terminal corrosion, or terminal damage present?

--

Go to Step 15

Go to Step 11

7

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the PCM connector C1.
  3. Use the J 39200 in order to measure the resistance between the following components:
  4. • The 8-way EBCM/EBTCM harness connector C3 terminal B
    • The PCM harness connector C1 terminal 14.

Is the resistance within the specified range?

0.0-2.0 ohms

Go to Step 8

Go to Step 13

8

Use the J 39200 in order to measure the resistance between the following components the 8-way EBCM/EBTCM harness connector terminal B and ground.

Is the resistance within the specified range?

OL

(Infinite)

Go to Step 9

Go to Step 14

9

  1. Inspect the following terminals:
  2. The 8-way EBCM/EBTCM harness connector C3 terminal B
  3. The PCM harness connector C1 terminal 14
  4. The remaining terminals of the 8-way EBCM/EBTCM harness connector C1
  5. Inspect the above terminals for the following conditions:
  6. • Damage
    • Poor terminal contact
    • Corrosion

Do any of the terminals exhibit poor terminal contact or corrosion, or damage?

--

Go to Step 15

Go to Step 10

10

  1. Reconnect the PCM connector C1.
  2. Reconnect the 8-way EBCM/EBTCM connector C3.
  3. Install a Scan Tool .
  4. Turn the ignition switch to the RUN position.
  5. Do not start the engine.

  6. Use the Scan Tool in order to read the DTCs.

Does DTC C1324 reset?

--

Go to Step 16

Go to Step 17

11

  1. Reconnect the PCM connector C1.
  2. Reconnect the 8-way EBCM/EBTCM connector C3.
  3. Install a Scan Tool .
  4. Turn the ignition switch to the RUN position.
  5. Do not start the engine

  6. Use the Scan Tool in order to read the DTCs.

Does DTC C1324 reset?

--

Go to Step 19

Go to Step 17

12

Repair the short to voltage in CKT 463.

Is the repair complete?

--

Go to Diagnostic System Check

--

13

Repair the open or the high resistance in CKT 463.

Is the repair complete?

--

Go to Diagnostic System Check

--

14

Repair the short to ground in CKT 463.

Is the repair complete?

--

Go to Diagnostic System Check

--

15

Replace all the terminals or the connectors that exhibit the following conditions:

    • Poor terminal contact
    • Terminal corrosion
    • Damage

Is the repair complete?

--

Go to Diagnostic System Check

--

16

Inspect the PCM. Go to Engine Controls.

Is the diagnosis complete?

--

Go to Diagnostic System Check

--

17

Replace the EBCM/EBTCM.

Is the repair complete?

--

Go to Diagnostic System Check

--

18

Repair the ground as necessary. Refer to Repair Procedures Cell 5 in Electrical Diagnosis.

Is the repair complete?

--

Go to Diagnostic System Check

--

19

The malfunction is intermittent or is not present at this time.

Is the repair complete?

--

Go to Diagnostic Aids

--