GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2001 🢒 Grand Prix 🢒 Brakes 🢒 Antilock Brake System 🢒 Traction Off Indicator Always On

Circuit Description

The TRAC OFF indicator is controlled by the EBCM. The EBCM supplies the ground to the Trac Off indicator control circuit to turn the indicator on. When the Trac Off indicator control circuit is not grounded at the EBCM, the TRAC OFF indicator remains off. When the EBCM sees the traction control switch voltage go low, it turns the TRAC OFF indicator on and disables traction control.

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.
    • Thoroughly inspect any circuitry that may be causing the 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
    • The following conditions may cause an intermittent malfunction:
       - A poor connection
       - Rubbed-through wire insulation
       - A broken wire inside the insulation
    • If an intermittent malfunction exists refer to General Electrical Diagnosis in Wiring Systems for further diagnosis.

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. This step checks for an internal EBCM malfunction.

    2.

  2. This step checks for an open in the Trac Off indicator control circuit.

Step

Action

Value(s)

Yes

No

Schematic Reference: Antilock Brake System Schematics

1

Was the Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check - ABS

2
  1. Turn the ignition switch to the RUN position, engine off.
  2. Using a scan tool enter ABS/TCS Data List.
  3. While monitoring the TRAC On/Off switch status, press and release the TRAC On/Off switch.

Does the switch status change from pressed to released as the TRAC switch is pressed and released?

--

Go to Step 3

Go to Step 8

3

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the EBCM connector C1.
  3. Install the Universal Pinout Box J 39700 using the J 39700-530 cable adapter to connector C1 only.
  4. Connect a fused jumper wire between terminals 18 and 15 of the Universal Pinout Box
  5. Turn the ignition switch to the RUN position, engine off.

Does the TRAC OFF Indicator turn on?

--

Go to Step 4

Go to Step 5

4

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

Is the replacement complete?

--

Go to Step 10

--

5

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the Driver Information Display (Base) or Trip Computer (Up Level) connector. Refer to Instrument Panel, Gages, and Console Connector End Views in Instrument Panel, Gauges and Console for connector pinout.
  3. Using the DMM, measure the resistance between terminals 18 of the Universal Pinout Box and the Driver Information Display (Base) or Trip Computer (Up Level) harness connector terminal L (Driver Information Display) or A6 (Trip Computer).

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

0-5ohms

Go to Step 7

Go to Step 6

6

Repair Traction Indicator control circuit for an open or high resistance. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 10

--

7

Suspect the Driver Information Display (Base) or Trip Computer (Up Level). Refer to Driver Information Center Module Replacement in Instrument Panel, Gauges and Console.

Is the repair complete?

--

Go to Step 10

--

8
  1. Turn the ignition switch to the OFF position.
  2. Disconnect the EBCM connector C1.
  3. Install the Universal Pinout Box J 39700 using the J 39700-530 cable adapter to connector C1 only.
  4. Using the DMM, measure the resistance between terminals 17 and 15 of the Universal Pinout Box while an assistant presses the TRAC On/Off switch.

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

0-5ohms

Go to Step 4

Go to Step 9

9

Repair Traction Control switch signal circuit for an open or high resistance, being sure to check the traction control switch for an open. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 10

--

10

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2