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Required Hardware - Volt & Other ASCM/SDGM Cars

The Volt has a number of possible configurations. This page lists the recommended method per car type, and all possible methods.

There are two parts to OpenPilot control: Lateral Control (Steering) & Longitudinal Control (Gas/Brake).

ASCM & SDGM give the comma control over steering. Your car's ACC will function as normal.

SASCM allows you to override the built in ACC and use OpenPilot Longitudinal control. If you have stock ACC and do not wish to use OpenPilot Long, you can just purchase the ASCM/SDGM portion of the suggestions.

Tip

We recommend purchasing from BearTechWorkshop (aka tinybear) whenever possible. They are a small business providing the openpilot community with high quality products and excellent customer support.

Comma Power is not needed

The Comma Power cable is not needed for most GM vehicles (eg. bolt and volt).

The 12V power is provided by the camera harness (or OBD for non-LKAS vehicles) and remains on while the car is powered off.

ASCM Harness & SASCM

Purchase List

  1. Comma 3X
  2. ASCM Harness Plus + Harness Box
  3. SASCM
  4. OBD-C Cable - 15 ft
  5. Optional: Comma Pedal for the ability to start from a stop in 2018 and up Volts

Reference Connection Diagram

Reference diagram

SDGM Harness & SASCM

Purchase List

  1. Comma 3X
  2. SDGM Harness + Harness Box
  3. SASCM
  4. OBD-C Cable - 10 ft
  5. Optional: Comma Pedal for the ability to start from a stop

Volts without ACC

Purchase List

  1. Comma 3X
  2. Choose a harness:
    1. OBD-II Harness
    2. GM Harness/Harness box (only for Volts with stock LKAS)
  3. Optional: Comma Pedal for the ability to start from a stop in 2018 and up Volts

Lateral (steering) control:

  1. If you have stock LKAS, your volt is capable of openpilot lateral control.
  2. If not, you need to flash LKAS firmware

Longitudinal (gas/brake) control:

  1. Flashing your Volt firmware for ACC. This will give you the best openpilot experience.
  2. Redneck ACC
  3. A potential option is the Comma Pedal , but you will be limited to L mode regen. This is completely untested and undeveloped in the Volt. Feel free to contribute!

Flashing Volt Firmware

pinballben is the resident expert on flashing Volt firmware, who will provide the instructions and hardware for a fee. DM on discord (through the member list of the frogpilot discord).

Flashing ACC

Flashing ACC will remove stock CC. This can be restored by re-flashing stock firmware.