What indicates a reversing polarity door lock system without an onboard computer in the circuit?

A reversing polarity door lock system without an onboard computer typically uses a setup that requires multiple wires to facilitate the operation of the door locks. In this case, having five wires at the switch is indicative of this type of system.

The three wires at the switch would not provide the necessary connections for both the lock and unlock functions, making it unsuitable for a reversing polarity system where the same wires are used for both operations but the polarity is reversed to actuate locks in different directions. In contrast, four wires could allow for separate lock and unlock functions, but may still not adequately address the complexity and functionality of a true reversing polarity system.

With five wires, you generally have the correct configuration to control the door locks effectively. This includes power and ground connections, as well as the two control wires needed to switch the polarity for both locking and unlocking mechanisms. This configuration allows for a more reliable and functional system that can operate without the need for an onboard computer, as all necessary controls are managed through the physical wiring alone.