GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC C0267 00: Low Brake Fluid Indicated

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Signal

C0267 00

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Ground

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Circuit/System Description

The brake fluid level switch monitors the level of brake fluid in the brake fluid reservoir. When the electronic brake control module (EBCM) sees the brake fluid level switch input closed, the DTC is set.

Conditions for Running the DTC

Ignition ON

Conditions for Setting the DTC

    • A short to ground is detected on the brake fluid level signal circuit for 5 s.
    • Low brake fluid level is detected for 5 s.

Conditions for Clearing the DTC

The condition for setting the DTC is no longer present.

Reference Information

Schematic Reference

Hydraulic Brake Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Hydraulic Brake System Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Inspect for proper brake fluid level. The fluid level should be above minimum level.
  2. If low, refer to Brake Fluid Loss.
  3. Ignition ON, observe the scan tool Brake Fluid Level Sensor parameter. The reading should be OK.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the B20 Brake Fluid Level Switch.
  2. Test for less than 5 Ω between the ground circuit terminal 2 and ground.
  3. If greater than the specified value, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify the scan tool Brake Fluid Level Sensor parameter is OK.
  5. If not the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the K17 Electronic Brake Control Module (EBCM).
  6. Install a 3 A fused jumper wire between the signal circuit terminal 1 and ground.
  7. Verify the scan tool Brake Fluid Level Sensor parameter is Low.
  8. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K17 Electronic Brake Control Module (EBCM).
  9. If all circuits test normal, test or replace the B20 Brake Fluid Level Switch.

Component Testing

Static Test

  1. Ignition OFF, disconnect the harness connector at the B20 Brake Fluid Level Switch.
  2. Test for infinite resistance between the ground circuit terminal 2 and the signal circuit terminal 1.
  3. If less than the specified value, replace the B20 Brake Fluid Level Switch.

Repair Instructions

    • Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
    •  Brake Fluid Level Indicator Switch Replacement
    •  Control Module References for EBCM replacement, setup and programming