In a 4-wire intake air pressure sensor, how many wires will have voltage when the connector is unloaded?

In a 4-wire intake air pressure sensor, typically there will be a configuration that includes wires for power, ground, a signal, and a signal return. When the connector is unloaded, meaning that it is not connected to any electrical circuit (like the vehicle’s wiring harness), the wires responsible for power and signal generation would still have voltage present.

Among the four wires, one is generally dedicated to the voltage supply, while another might carry the output signal. The other two wires often include a ground and a signal return. In this scenario, both the power wire and the signal wire will exhibit voltage when the connector is disconnected because they are not influenced by the connection to the ground or the rest of the circuit.

Consequently, the answer indicates that when the connector is unloaded, the two wires carrying voltage, plus potentially the ground wire under certain conditions, can be considered, leading to the conclusion that three wires in total could have voltage when measured in this state. This understanding of voltage presence in various configurations is crucial for diagnosing automotive sensor systems effectively.