For users of OBD2 adapters, especially those utilizing Bluetooth connectivity with devices like the Galaxy S3 and apps such as Turbo3’s, maintaining a stable and reliable connection is paramount. The BAFX Products PIC18F2480 Bluetooth OBD2 adapter has garnered positive reviews for its solid performance and compatibility. However, a common concern with OBD2 adapters is their constant draw on the car battery, even when the vehicle is turned off. This article provides a straightforward guide to modify your BAFX Bluetooth OBD2 adapter for switched 12V power, ensuring it only operates when your vehicle is running or in ACC mode. This modification is particularly beneficial in preventing unnecessary battery drain.
This modification is surprisingly simple and can be completed in approximately 15 minutes with basic tools. Follow these steps to convert your BAFX Bluetooth OBD2 adapter to switched power.
Step-by-Step Guide to Modify Your BAFX Bluetooth OBD2 Adapter
-
Open the Adapter Casing
The BAFX adapter’s housing is secured with four screws located beneath the blue label. Carefully peel off the adhesive label to access these screws. Once exposed, use a small screwdriver to remove all four screws.
-
Disconnect the Internal Connector
After removing the screws, gently separate the two halves of the adapter’s casing. Inside, you will see a white connector attaching the OBDII port to the PC board. Carefully unplug this white connector from the PC board to detach the OBDII connector assembly.
-
Remove the OBDII Connector Assembly
With the connector unplugged, you can now lift the entire OBDII connector assembly completely out of the adapter’s shell. This provides clear access to the wiring for modification.
-
Wire Modification: Swapping Pin 16 to Pin 8
This is the core of the modification. Locate pin 16 and pin 8 on the OBDII connector. Pin 16 is typically wired for constant 12V power, while pin 8 is designated for switched ACC 12V power. In most standard OBDII connectors, pin 16 is situated at the top left, and pin 8 is at the bottom left when viewed from the wiring side as shown in the image below.
Carefully move the wire currently connected to pin 16 and insert it into the pin 8 slot. This reroutes the power source for the adapter from a constant to a switched supply.
-
Reassemble the Adapter
Place the OBDII connector assembly back into the shell and reconnect the white connector to the PC board. Carefully align the two halves of the adapter casing and reattach them using the four screws. Ensure you don’t bend the five LEDs on the board during reassembly.
-
Final Touches and Testing
Replace the blue label if desired, or leave it off. Your BAFX Bluetooth OBD2 adapter is now modified for switched power. Test the adapter in your vehicle to ensure it powers on and functions correctly only when the ignition is turned on or in ACC mode. It should now operate as intended, but only drawing power when the vehicle is running, effectively preventing battery drain when the vehicle is off.
This modification ensures your Bafx Products Bluetooth Obd2 adapter is only active when needed, preserving your car battery and providing peace of mind.
