Accessport Quick Start Guide

Looking for power gains or what to flash to your car?


What’s in the Box?

Accessport V3







The Accessport (AP) is a handheld device that can flash or reprogram your vehicle’s computer with various performance, or even non-performance maps (tuning files) all through the vehicle’s on-board dignostic port (OBDII Port).

Manufacturers have very different names to call a car’s computer (and all insist that their way is correct).

ECU, ECM, PCM, DME are just a few of the options.

Once installed to a vehicle, in addition to changing the maps, the Accessport can display live vehicle data on gauges, take performance measurements, read and clear check engine lights (trouble codes, DTC, CEL) and more!

For questions on terminology check out the bottom of the page, or if you have any questions, please contact our support team: | 866-922-3059 |


The Accessport can only be installed to one vehicle at a time. Once installed to a car by flashing it for the first time, the Accessport is now paired or married to that car and will not be able to flash a different vehicle until it has gone through the uninstall option to become unmarried.

During initial installation or uninstall it is important that the vehicle’s battery has adequate power for the ECU to allow itself to be flashed, and for the car to maintain power and not potentially die during the flashing process. To prevent issues, make sure the lights, stereo, and climate control are all turned off during the process. Using a 10-20 amp battery charger (not a tender or jump pack) is a requirement for most installation and uninstallation processes to ensure stable power.


  1. Park your car in a safe area, preferably not at a random gas station in the middle of the desert.

  2. Hook the car up to a 10-20 amp charger (not a tender or jump pack.

  3. Once the vehicle is hooked up to a charger, locate the car’s OBDII port (typically under the dash on the driver’s side) and plug in the supplied OBDII cable. If you need help locating the port check out our page . Make sure to remove any other items that may be communicating via the obdII port or over CAN as they can cause interference. Including but not limited to LoJack, P3 Gauges, OBD splitters, head units that display data from the engine, radar detectors, or any kind of piggy back or other tune.

  4. Connect the small end of the OBDII cable to the accessport making sure it is in all the way with the arrow on the top side (glass side) of the Accessport.


  5. SUB-001, SUB-002 ONLY: locate and connect the two green Test Mode connectors under the dash towards the left kick panel. To ensure the connection is made, turn the key to the ON position but do NOT start the engine. You should hear the radiator fans and fuel pump cycling on/off as well as notice the ‘Check Engine’ light flashing. This is normal and confirms that the vehicle is in Test Mode. Once Test Mode is confirmed, turn the key back to the OFF position and continue. These will need to be connected whenever changing a base map.


    2002-2005 WRX will need to connect one of the provided Initialization Connectors. The corresponding connector is located under the driver’s side lower dash near the green Test Mode connectors and is translucent white.


  6. 2020-2021 Civic Type R Only

  7. Turn the car on (not started). This means either rotating the key to the on position, or typically pressing the start/stop button twice with your foot off the brake.

  8. Select the Install option on the Accessport to begin the install process.


  9. When you first install the Accessport by selecting Install from the main menu, the Accessport will recognize your vehicle and offer the proper maps for your car.

  10. Map Selection: After selecting install you’ll end up on the map selection screen. Once there you will then choose which map you want to flash and select it using the center button. For more information on the map availability, what they work with, and power gains check out our map notes

  11. Once the map is selected, the accessport will copy what the stock ECU file was and flash your vehicle’s ECU with the map you select. This process pairs (marries, installs) the Accessport to your vehicle and it will remain this way until you uninstall the Accessport from the vehicle. An Accessport can only be used on one vehicle at a time.

  12. Follow all the prompts carefully before clicking the center OK button during the flash. Some vehicles will take a while for the initial installation, however subsequent flashes will be faster, this is part of why the charger is a requirement for initial installation and uninstall.

  13. Once finished with the flash the Accessport will clear engine codes, then prompt you to leave the car turned off for at least 10 seconds before starting. Then you’re all done!


Do not disturb the Accessport, OBD-II cable, or open or close vehicle doors while installation is taking place. For vehicles with push to start make sure the key is in the vehicle at all times. Failure to do so may result in incomplete ECU reprogramming which will render the vehicle inoperable.

Additional Reference Items

  • For additional help with your vehicle’s Accessport

  • Home page for COBB Support of all kinds

  • Information on maps for your vehicle

CARB Sticker Application

(Where Applicable)

Apply the supplied CARB sticker in a clear, easy to find location.  Typically underhood, or on the radiator core support.


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