The OBD2 port, short for On-Board Diagnostics port, is a standardized 16-pin connector found in most vehicles manufactured after 1996. Its primary function is to provide access to vehicle diagnostic data. A common question among car owners, especially those using dashcams or other devices powered through this port, is whether the OBD2 port is always powered. The answer is: it depends.
While the OBD2 port is often powered even when the ignition is off, this isn’t universally true. Some manufacturers choose to power the port only when the ignition is switched on. This variability depends on the car make, model, and year. Therefore, assuming constant power can lead to a drained car battery if a device is left plugged in continuously.
For devices like dashcams that require continuous power for parking mode surveillance, understanding your vehicle’s specific OBD2 power behavior is crucial. If your OBD2 port is always on, you can use a low-voltage cutoff device like the Koolatron Battery Saver. This device, readily available online, plugs into the cigarette lighter socket and incorporates a switch to cut power to connected devices when the battery voltage drops below a certain threshold, typically around 11.6 volts, preventing a dead battery.
If your OBD2 port is only powered with the ignition, several options exist for powering your dashcam. You can use a dedicated OBD2 power adapter with a built-in low-voltage cutoff. These adapters are readily available and inexpensive. Alternatively, you could run a USB power line from the dashcam to a hidden location under your dash and use a separate OBD2 adapter only when needed for parking surveillance.
When utilizing the always-on cigarette lighter socket for powering a dashcam and other devices, consider using a heavy-duty splitter rated for at least 10 amps. This allows you to connect multiple devices safely. Plug the low-voltage cutoff device into one port of the splitter and your dashcam’s USB adapter into the cutoff device. The other port remains free for charging phones or other accessories.
Using the OBD2 port for powering devices like dashcams doesn’t typically overload the system. The OBD2 port is designed to provide up to 4 amps, and most dual dashcam setups require 2 amps or less. Furthermore, removing the adapter when you need to use the OBD2 port for diagnostic scanning is easy. Simply unplug the adapter and connect your scanner.
