GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The electronic brake control module (EBCM) monitors the brake fluid level in the master cylinder reservoir via the brake fluid level switch.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0267 Low Brake Fluid Indicated

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The EBCM detects a low brake fluid level condition.

Action Taken When the DTC Sets

The brake warning indicator turns ON.

Conditions for Clearing the DTC

The conditions for setting the DTC are no longer present and you use the scan tool Clear DTCs function.

Diagnostic Aids

A lower than normal brake fluid level in the master cylinder may cause the brake fluid level switch to close when the vehicle makes sharp turns or sudden stops. Low brake fluid level may be caused by a brake fluid leak or worn disc brake pads. Thoroughly inspect connections or circuitry that may cause an intermittent malfunction. Refer to the following:

    •  Testing for Electrical Intermittents
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs
    •  Connector Repairs

Step

Action

Yes

No

Schematic Reference: Brake Warning System Schematics

Connector End Views Reference: Hydraulic Brake Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Use a 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 set?

Go to Step 3

Go to Diagnostic Aids

3

Inspect the brake fluid level in the master cylinder reservoir. Refer to Master Cylinder Reservoir Filling .

Did you find and correct the condition?

Go to Step 8

Go to Step 4

4

  1. Disconnect the brake fluid level switch harness connector.
  2. Use the scan tool to observe the Brake Fluid Level status.

Does the scan tool display Low?

Go to Step 6

Go to Step 5

5

Replace the brake fluid level switch. Refer to Brake Fluid Level Indicator Switch Replacement .

Did you complete the replacement?

Go to Step 8

--

6

  1. Turn OFF the ignition.
  2. Disconnect the electronic brake control module (EBCM) harness connector.
  3. Test the brake warning indicator supply voltage 1 circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 8

Go to Step 7

7

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

Did you complete the replacement?

Go to Step 8

--

8

  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 3

System OK