Tesla doesn't use a traditional 12V accessory outlet. What are my options?

Modified on Thu, 28 May at 10:55 AM

While Tesla's do have a low-voltage accessory battery apart from the vehicle's main motor battery, newer Tesla models (possibly including but not limited to the 3 and Y) feature an accessory battery running 15.5V or 16V instead of the traditional 12V lead-acid system.

Why the voltage matters

Our detectors have a 15.5V ±0.5V power cap, meaning that they will reach their maximum input voltage when connected to a newer Tesla 15.5V accessory battery.

What happens when high voltage is detected

Our radar detectors can sense when the maximum input voltage is reached (which may vary ±0.5V, so depending on circumstances this may be in the range of 15V to 16V) and will display a message indicating the high voltage condition, and subsequently shut down to avoid internal damage.

Why is this behavior inconsistent in my vehicle

You may notice our devices operate normally, but intermittently shut down due to high voltage conditions. This can be caused by a few conditions including:

Recharging: The accessory battery in a Tesla is recharged by the main system battery. Voltage can temporarily spike or long term increase during these charge cycles, causing our devices to shut down.
Power Spikes and Excessive Drain: Other devices operating on the accessory battery can pull larger power loads, dividing what is available to other devices and bringing down the voltage slightly. Likewise when the devices cycle off or are unplugged, voltage can increase to normal levels. These fluctuations may cause our devices to shut down.

What are my options with a 15.5V or 16V battery?

If you have this type of accessory battery causing the high voltage conditions, you have several options.

USB-C to RJ11 power cord: USB-C ports operate at 5V and should be available in your Tesla, with the output voltage restricted to 5V. Although 5V is too low to operate our units without a special cable, we have a power cord capable of stepping up the voltage to 12V and providing the power needed to operate our detectors. Get the USB-C to RJ11 power cord here.
- The USB-C to RJ11 is 3' 11" in length, and does NOT include alert lights and mute button like our SmartCords have; a SmartCord version is not currently available.
- The conversion to 12V requires 2.5A of power from the vehicle's USB-C port, which your Tesla should provide. If you find there is an issue, there may be too many devices plugged into various USB-C ports in the vehicle (USB is designed to share power between connections.) Additionally, some vehicles may also not provide a full 2.5A of power, please consult your manual or dealership for specifics before purchase.
Step Down Voltage Regulator: This device (sometimes referred to as a converter) can be installed on the accessory battery system to safely pull down voltage to 12V or 13.8V levels in order to power our units as well as many other devices without causing interna damage.
- Please be sure an approved device is installed by your dealership or a qualified professional.

Better alternatives

To get around the power issues as well as not have a detector blocking your view on the window, consider an installed system which are radar detectors installed by professionals and custom-integrated into your vehicle.

Installed systems also avoids the issues with a solarized windshield also found in many Tesla models, so they are a great option for any Tesla.

Our current model Redline Ci 360c includes weatherproof sensors mounted in your front bumper (with optional rear sensors) and a hidden display inside the cabin. These systems also include Laser Shifters to scramble or "jam" Laser (aka LIDAR) detection, if legal in your state.

We partner with a number of dealers who are capable of installation with the appropriate step down voltage regulator as required. Find a dealer local to your area here for pricing and information.