GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The ignition is ON and battery voltage is applied to terminal 15 of the electronic brake control module (EBCM). The EBCM proceeds the self-test about the main relay in the EBCM.

Conditions for Running the DTC

If the EBCM proceeds the self-test about the main relay and senses the fault, the EBCM may make the fault code.

Conditions for Setting the DTC

EBCM internal fault

Action Taken When the DTC Sets

The antilock brake system (ABS) warning lamp is ON.

This is a critical operational fault. The ABS is disabled and the ABS warning lamp is turned ON. The proportioning is operation.

Step

Action

Values

Yes

No

Schematic Reference: Antilock Brake System Schematics

Connector End View Reference: Antilock Brake System Connector End Views

1

  1. Turn the ignition switch to OFF.
  2. Disconnect the EBCM harness connector.
  3. Turn the ignition switch to ON.
  4. Use a digital voltmeter (DVM) to measure the voltage between terminal 15 and terminal 19 of the EBCM connector.

Is the voltage within the specified value?

10.5-13.5 V

Go to Step 2

Go to Step 3

2

Replace the EBCM.

Is the repair complete?

--

System OK

--

3

  1. Turn the ignition switch to OFF.
  2. Remove the fuse Ef4 in the engine fuse block.
  3. Check for an open in fuse Ef4.

Is the fuse open?

--

Go to Step 5

Go to Step 4

4

Replace the fuse Ef4.

Is the repair complete?

--

System OK

--

5

Use a DVM to measure the resistance between ground and terminal 19 of the EBCM harness connector.

Is the resistance less than the specified value?

0.05 ohms

Go to Step 7

Go to Step 6

6

Repair the open between terminal 19 of the EBCM connector and ground G101.

Is the repair complete?

--

System OK

--

7

  1. Turn the ignition switch to OFF.
  2. Disconnect the connector C205 next the I/P fuse box.
  3. Turn the ignition switch to ON.
  4. Use a DVM to measure the voltage between ground and terminal 1 of the connector C205.

Is the voltage within the specified value?

10.5-13.5 V

Go to Step 9

Go to Step 8

8

Repair the open between the ignition switch (IGN 1) and terminal 1 of the connector C205.

Is the repair complete?

--

System OK

--

9

  1. Inspect the open between fuse Ef4 input and terminal 1 of the connector C205.
  2. Inspect the open between fuse Ef4 output and terminal 15 of the EBCM connector.
  3. Repair or replace the fault.

Is the repair complete?

--

System OK

--