1. Pre-Installation Safety & Tool Checklist

Installing the BlackVue OBD-II Power Cable requires no special electrical tools, wire strippers, or fuse taps. Before beginning, ensure you have:

1. Your BlackVue 3-wire dashcam main unit and mounting bracket.
2. The BlackVue OBD-II Power Cable (BOC-300 or BOC-400) with 3.0m cable.
3. The included plastic trim pry tool and adhesive cable clips.

2. Step-by-Step Cable Installation

Follow these steps for a clean, hidden installation:

1. Locate the OBD-II Port: Locate your vehicle's standard 16-pin OBD-II diagnostic port. It is typically positioned underneath the driver-side dashboard, above the foot pedals, or behind a removable plastic fuse panel cover.
2. Plug in the Adapter: Firmly press the BOC-300 or BOC-400 connector into the vehicle's OBD-II port until it seats securely.
3. Route the Power Cable:
   • Run the 3.0-meter cable up the driver-side A-pillar weatherstripping.
   • Tuck the wire cleanly behind interior trim panels and along the front headliner toward the windshield-mounted dashcam.
4. Connect to Dashcam: Plug the 3-pin DC barrel jack directly into the DC-in port of your BlackVue dashcam.

3. BOC-400 Initial Drive Calibration

The BOC-400 incorporates a 3-axis MEMS accelerometer alongside OBD pin signal monitoring. To ensure accurate movement detection:

1. Insert the BOC-400 into the OBD-II port while the vehicle ignition is ON.
2. Observe the status LED on the BOC-400 body:
   • Blinking LED: Indicates that the MEMS accelerometer is calibrating its movement vector.
3. Drive the vehicle forward for 1 to 2 meters.
4. Once movement is registered, the LED will transition to Solid ON, signaling that sensor calibration is complete and active.

4. Operational State Transitions (How Parking Mode Works)

The OBD-II cable automatically manages the state transitions between driving and parking modes:

Normal Driving Mode (ACC-High)

• Trigger: Ignition turned ON or physical vehicle movement detected.
• Dashcam Response: Dashcam records continuously in Normal Loop Recording.
• LED Indicator:
  • BOC-300: Solid ON immediately upon detecting ignition signal.
  • BOC-400: Solid ON once MEMS calibration is verified (Blinking during initial calibration).

Parking Mode Transition (ACC-Low)

• Trigger: Ignition turned OFF.
• Transition Timings:
  • Standard Ignition OFF: The cable detects the drop in ignition signal on the OBD bus and transitions the camera into Parking Mode within 2 minutes (voltage-based check).
  • Smart Key & Remote Door Lock: On vehicles equipped with keyless entry systems, locking the vehicle doors via remote key accelerates the Parking Mode transition to approximately 30 seconds.
  • Maximum Delay Check: Internal safety logic holds for a maximum of 10 minutes depending on residual vehicle ECU bus voltage decay.
• LED Indicator: BOC-300 and BOC-400 status LEDs turn Solid OFF in ACC-Low.

5. Vehicle Event Behaviors

Modern vehicle electronics can cause temporary state changes during parking:

• Periodic ECU Wake-Up (2023 Audi A6): The 2023 Audi A6 ECU executes a brief 5-second system wake-up check every 1 hour while parked. During this 5-second window, the cable briefly enters Driving Mode before automatically returning to Parking Mode. This is normal vehicle behavior.
• Door or Trunk Opening: Opening a vehicle door or trunk wakes up the interior CAN-bus network, causing the cable to temporarily switch the dashcam to Driving Mode. It automatically re-enters Parking Mode after the door is closed.
• Smart Key Proximity: Approaching your vehicle with a smart key fob (within 2 meters) may wake up the vehicle's diagnostic bus and trigger ACC-High. Walking away restores ACC-Low within 10 minutes (on BYD vehicles like the ATTO3, the remote key must be >2m away to allow ACC-Off recognition).