System Pre Check

Connector Diagram:

DESCRIPTION
Code 12 is generated when the anti-lock electronic control unit detects that the brake fluid level in the brake master cylinder reservoir is low for one or more seconds during an anti-lock stop. It can also be generated by a short in the stoplight circuit.

POSSIBLE CONTRIBUTING BASE BRAKE COMPONENT/VEHICLE WIRING CONCERNS
- Low master cylinder fill level
- Fluid leaks in vehicle brake system
- Worn or damaged master cylinder fluid level switch, or fluid level circuit shorted to ground
- Master cylinder float that sticks in the bottom of brake master cylinder reservoir or does not float
- Failed diode-resistor element in stoplight circuit