GM Service Manual Online
For 1990-2009 cars only

Circuit Description

During calibration of the offset of the pressure sensor signal, the pressure sensor signal offset value must be in the range of 1-15 Bar (1-434 psi).

The pressure sensor is also monitored for sensitivity via a correlation between estimated vehicle deceleration and the pressure sensor signal. This is monitored over the course of numerous straight line non antilock brake system (ABS) braking stops.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

DTC C0132 Antilock Brake System (ABS)/Traction Control System (TCS) Pressure Circuit Range/Performance

Conditions for Running the DTC

    • The ignition is ON.
    • The vehicle speed is greater than 40 km/h (25 mph).

Conditions for Setting the DTC

    • The sensor signal offset value is out of range for more than 1 second.
    • The brake pedal is not applied.
    • The ABS pump is not ON.
    • The brake pressure sensor sensitivity is outside a predetermined range.
    • The brake pressure sensor indicates low brake fluid pressure, and the brake pedal position sensor indicates brakes applied.

Action Taken When the DTC Sets

If equipped, the following actions occur:

    • The electronic brake control module (EBCM) disables the ABS/traction control system (TCS)/vehicle stability enhancement system (VSES) for the duration of the ignition cycle.
    • A malfunction DTC will set.
    • The ABS indicator turns ON.
    • The Stability Off indicator turns ON.
    • The red BRAKE warning indicator could turn ON.

Conditions for Clearing the DTC

    • The condition for the DTC is no longer present.
    • A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
    • Using a scan tool

Diagnostic Aids

    • A malfunctioning pressure sensor
    • A malfunctioning EBCM
    • Test the brake pedal position sensor (BPPS) for proper operation, and adjustment. An improperly adjusted BPPS will set the DTC.

Test Description

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

  1. This step tests for DTCs set in the Body Control Module BCM Lighting Systems for a malfunctioning BPPS.

  2. This step tests for specified voltage on the brake pressure signal circuit.

  3. This step checks to see if voltage was below specified voltage.

  4. This step checks to see if voltage was above specified voltage.

  5. This step checks to see if voltage was above specified voltage of the 5-volt reference.

  6. This step checks to see if 5-volt reference from the EBCM is 5 volts.

  7. This step checks to see if resistance of the ground circuit is less than 5 ohms.

  8. This step tests for a short to voltage in the 5-volt reference circuit.

  9. This step tests for a short to ground, a high resistance, or an open in the 5-volt reference circuit.

  10. This step tests for a short to voltage in the brake pressure sensor signal circuit.

  11. This step tests for a high resistance or an open in the ground circuit.

  12. This step checks the brake pressure sensor connector for poor connections.

  13. This step checks to EBCM connector for poor connections.

Step

Action

Value(s)

Yes

No

Schematic Reference: Antilock Brake System Schematics

Connector End View Reference: Antilock Brake System Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle

2

After performing the Diagnostic System Check, retrieve DTCs set for the brake pedal position sensor (BPPS).

Did the BPPS set DTCs?

--

Go to Diagnostic Trouble Code (DTC) List - Vehicle

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the electronic brake control module (EBCM).
  3. Install the J 39700 Universal Pinout Box with the J 39700-530 Cable Adapter between the EBCM and the EBCM harness connector.
  4. Turn ON the ignition, with the engine OFF.
  5. Using the DMM, measure the voltage between pin 17 and pin 15 of the J 39700 .

Is the voltage within the specified value?

0.25-4.75 V

Go to Diagnostic Aids

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the brake pressure sensor.
  3. Turn ON the ignition, with the engine OFF.
  4. Using the DMM, measure the voltage between pin 17 and pin 15 of the J 39700 .

Is the voltage less than the specified value?

4.75 V

Go to Step 5

Go to Step 11

5

  1. Turn OFF the ignition.
  2. Connect a 3-amp fused jumper wire between the 5-volt reference circuit of the brake pressure sensor and the signal circuit of the brake pressure sensor.
  3. Turn ON the ignition, with the engine OFF.
  4. Using the DMM, measure the voltage between pin 17 and pin 15 of the J 39700 .

Is the voltage greater than the specified value?

0.25 V

Go to Step 6

Go to Step 9

6

  1. Disconnect the fused jumper wire.
  2. Measure the voltage between the 5-volt reference circuit of the brake pressure sensor and the ground circuit of the brake pressure sensor.

Does the voltage measure less than the specified value?

5 V

Go to Step 7

Go to Step 8

7

  1. Turn OFF the ignition.
  2. Disconnect the negative battery cable.
  3. Measure the resistance from the ground circuit of the brake pressure sensor to a good ground.

Does the resistance measure less than the specified value?

5 ohms

Go to Step 13

Go to Step 12

8

Test the 5-volt reference circuit of the brake pressure sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 17

Go to Step 14

9

Test the 5-volt reference circuit of the brake pressure sensor for a short to ground, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 17

Go to Step 10

10

Test the signal circuit of the brake pressure sensor for a short to ground, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 17

Go to Step 14

11

Test the signal circuit of the brake pressure sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 17

Go to Step 14

12

  1. Disconnect the EBCM.
  2. Test the ground circuit of the brake pressure sensor for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 17

Go to Step 14

13

Inspect for poor connections at the harness connector of the brake pressure sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 17

Go to Step 15

14

Inspect for poor connections at the harness connector of the EBCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 17

Go to Step 16

15

Replace the brake pressure sensor. Refer to Brake Pressure Modulator Valve Pressure Sensor Replacement .

Did you complete the replacement?

--

Go to Step 17

--

16

Important: Before replacing the EBCM, inspect the brake pedal position sensor for proper adjustment. Refer to Brake Pedal Position Sensor Calibration .

Replace the EBCM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

--

Go to Step 17

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17

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

--

Go to Step 2

System OK