OBD2 Diagnostic Cables and Gateway Bypass Adapters

Why some scan tools need a gateway bypass cable

Many Chrysler, Dodge, Jeep and Ram vehicles built from about 2018 have a Security Gateway module that blocks aftermarket scan tools from sending commands through the OBD-II port. Reading codes may still work, but resets, calibrations and other writes are refused. A bypass cable connects the tool to the network on the vehicle side of the gateway. Some tools instead log in through the maker's authentication service, which avoids the cable.

Connector layout, location and cable length

Titles name a layout such as 12+8 or 12+16, which describes the gateway connector, and the cable must match the one in your vehicle. The module sits behind the dash, usually near the diagnostic port, and its position varies by model, so expect to remove some trim. Check the cable length reaches your scan tool. Dash camera adapters list output power and plug type, which should match your camera's voltage and connector.

Questions about OBD2 Diagnostic Cables and Gateway Bypass Adapters

Does a bypass cable work on every Chrysler, Dodge, Jeep or Ram?

No. It is meant for vehicles fitted with the Security Gateway, mostly late-model years, and the connector layout differs by model. Match the cable's listed fitment and layout to your vehicle before ordering.

What do 12+8 and 12+16 mean?

They describe the connector layout on the cable, in pin groups. Different gateway modules use different plugs, so the right cable depends on your vehicle's module rather than the make alone.

Will a bypass cable let me change settings on my car?

It lets a compatible scan tool talk to the vehicle network, so functions such as resets and calibrations can be sent. What you can change still depends on the scan tool and the vehicle's own limits.