Navigating the electronic systems in modern vehicles like your 2015 Honda CRV can seem complex. One common point of interest for many car owners and DIY enthusiasts is the OBDII plug. You might have heard various things about this connector, and it’s understandable to have questions or even some misconceptions. Let’s clarify what the OBDII plug is, especially in the context of your 2015 Honda CRV, and address some common queries about its use, particularly regarding drawing power from it.
What Exactly is the OBDII Plug?
Technically referred to as an SAE J1962 connector, the OBDII plug is a standardized interface mandated in vehicles sold in the US from 1996 onwards. This standardization was implemented by the EPA to allow universal diagnostic scan tools to communicate with vehicle’s computer systems. The pin layout of this connector is precisely defined by SAE standards, ensuring compatibility across different makes and models, including your 2015 Honda CRV. Its primary purpose is for diagnostics, allowing mechanics and technicians to read trouble codes and access vehicle data using specialized scan tools.
Pin 16 and Power: Separating Fact from Fiction
Discussions often arise about pin 16 of the OBDII connector. It’s true that pin 16 provides 12V+ battery power. However, it’s crucial to understand its intended function. Pin 16 is designed solely to supply power to the diagnostic scan tool when it’s connected. It is directly connected to the vehicle’s battery power bus and nothing else. It doesn’t interact with any computer or electronic control unit in your 2015 Honda CRV beyond providing a direct power source.
While technically you could use pin 16 to power a low-draw aftermarket device, it’s generally not recommended and there are important considerations.
Why Using the OBDII Plug for Power is Discouraged
Although pin 16 provides battery voltage, utilizing it as a general power source is often advised against by automotive professionals. Here’s why:
- Risk of Misuse: The OBDII port is designed for diagnostics. Tampering with it for other purposes increases the risk of accidentally short-circuiting or damaging sensitive electronic systems if incorrect pins are used.
- Better Alternatives Exist: Your 2015 Honda CRV, like most modern vehicles, has a fuse box specifically designed to safely distribute power to various circuits. Tapping into the fuse box is a much safer and more appropriate method for powering aftermarket accessories. There are even specialized fuse taps that allow you to easily add a circuit without cutting or splicing wires.
- Grounding Considerations: The OBDII connector has two ground pins: pin 4 (chassis ground) and pin 5 (signal ground). While pin 4 is a suitable ground for powering a device, pin 5 is a sensitive signal ground used by the vehicle’s computer for sensor voltage references. Incorrectly using pin 5 as a ground can disrupt sensor readings and potentially cause diagnostic issues.
Instead of risking complications by using the OBDII plug for power, accessing power directly from the fuse box is a far safer and more reliable approach for any accessory you might want to install in your 2015 Honda CRV.
Safer Power Options for Your 2015 Honda CRV
For powering any aftermarket devices in your 2015 Honda CRV, the fuse box offers a more secure and intended method. You can easily locate your fuse box, usually under the dashboard or in the engine compartment. Many vehicles also have spare fuse slots for optional equipment that wasn’t installed, providing convenient points to draw power. Fuse taps are readily available and make it simple to add a new circuit while maintaining proper circuit protection.
In conclusion, while pin 16 of the OBDII plug on your 2015 Honda CRV does provide 12V power, it’s best reserved for its intended diagnostic purpose. For powering accessories, utilizing the fuse box is the recommended and safer practice, ensuring you avoid any potential electrical issues and maintain the integrity of your vehicle’s complex electronic systems.
