What Is a ‘CK Wired’ Bulb Socket?


CK Wired Bulb Sockets


  • All CK Sockets bulb connectors
    • Typically found in turn  signals, marking, and brake lights


What is a CK wired bulb socket, and why are they different than standard wired bulb sockets.


This image is only an example.

The simplest definition is a CK wired socket is one that is wired specifically for polarity sensitive light bulb uses. LED light bulbs, or light emitting diode bulbs, have built in circuitry for color and brightness and require a connection that is polarity sensitive or a bulb that has internal circuitry to adapt to a circuit that has not been specifically wired for the bulb type. A standard incandescent bulb in either the round base like an 1157, or wedge design such as the 3157 are not polarity sensitive type light bulbs. Simply connecting a positive to one side of the circuit and the other to a ground will illuminate the light bulb.

When upgrading or converting a standard incandescent bulb circuit to an LED type, determine if the LED bulb has the internal circuit to adapt to a common light circuit. If it does not, you must test and possibly rewire the connector to the specific LED light bulb circuit design. Special attention to how the socket is wired will prevent endless diagnosis and possible damage to the circuit fuse. The diagram below shows an example of the difference in wiring configurations. When testing sockets, it is important to remember to remove the other incandescent bulbs in the circuit as they will cause a false ground due to the non-polarity condition of a standard bulb.

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