top of page

911 Brake Ballast Resistor Pigtail Installation Instructions

 


INSTRUCTIONS:

 

  • Examine the brake ballast resistor pigtail. The red and black wires will go between the brake light switch and its connector located on the brake master cylinder in the front trunk.

  • The ballast resistors have an eye connector on the brown wire to be connected to a local chassis ground.

  • An extra brown wire is included for 911 cars with 3 terminal brake switches.

  • 2 wire switch instructions listed first; 3 wire switch instructions listed last.

  • Locate brake light switch on the brake master cylinder.

  • Pull the connector off.

2 Wire Switch

  • Notice the 2 wire colors on the connector.

  • The red pigtail wire goes to the GREEN/BLUE wire. Insert the male spade of the red wire.

  • The black pigtail wire goes to the BLACK/YELLOW wire. Insert the male spade of the black wire.

  • Connect the female spade connectors of the red and black wires to the brake light switch terminals on the brake master cylinder. It does not matter which wire goes to which switch terminal.

  • Connect the brown wire with the eye connector to a local chassis ground.

  • The pigtail is now connected.

  • Test the pigtail:

  1. Start the car. Apply parking brake. Do not press the brake pedal. The resistors should be cold.

  2. Now press and hold the brake pedal. The resistors should warm up and get hot.

  3. If the resistors get hot in 1) and cold in 2), swap the wires on the brake light PLUG.

  • The wiring is complete

  • With a tiewrap, secure the resistors to a local chassis brace.

  • DO NOT secure the resistors to other wiring. The resistor will get hot when the brake pedal is pressed for long periods​​​​

911 Brake Compatibility 3-Wire.jpg

3 Wire Switch

  • Notice the 3 wire colors on the connector and the 3 connections.

    • Pin 81: Vehicle wire BLACK/RED

    • Pin 81A: Vehicle wire RED

    • Pin 82A: Vehicle wire BLACK​

  • Disconnect the plug from the brake light switch found on the brake housing in the front trunk.

  • Connect the black and red wires of the ballast harness as shown below.

  • Using the extra brown wire, connect as shown below.

  • Connect the brown wire with the eye connector to a local chassis ground.

  • The wiring is complete

  • With a tiewrap, secure the resistors to a local chassis brace.

  • DO NOT secure the resistors to other wiring. The resistor will get hot when the brake pedal is pressed for long periods​​​​.

bottom of page