Bi-directional control, a key feature in advanced car diagnostic scanners, allows for two-way communication between the scanner and a vehicle’s computer system. Unlike basic OBD2 scanners that only read diagnostic trouble codes and data, bi-directional scanners can also send commands to activate specific components, enabling more comprehensive diagnostics. This functionality is often referred to as actuator tests, functional tests, or system tests. Even reprogramming falls under the umbrella of bi-directional control.
Understanding Bi-Directional Control in Car Scanners
A bi-directional scanner’s ability to send commands sets it apart from standard OBD2 scanners. It allows mechanics to actively test components, pinpointing malfunctions that might otherwise be missed. This two-way communication enables the scanner to both request information from the vehicle’s systems and relay instructions to perform specific actions. For instance, a mechanic can use bi-directional control to activate a relay fan or fuel pump, observing its operation for any anomalies.
An Innova 5610 bi-directional scanner performing diagnostics.
Examples of Bi-Directional Tests
The range of tests possible with bi-directional control varies depending on the vehicle and scanner model. Some common examples include:
- Activating Relays: Turning components like cooling fans, fuel pumps, and lights on and off to test functionality.
- Controlling Solenoids: Testing the operation of solenoids that control various systems like emissions, transmission, and engine management.
- Adjusting Actuators: Manipulating actuators like throttle valves and EGR valves to assess their response.
- Performing System Tests: Running specific system tests, such as EVAP system tests or ABS module tests, to diagnose problems.
- Reprogramming Modules: Updating or modifying vehicle control module software.
A bi-directional scanner being used to diagnose a purge valve.
Bi-Directional Scanners: Essential Tools for In-Depth Diagnostics
While basic OBD2 scanners provide valuable information, bi-directional scanners offer a deeper level of diagnostic capability. Their ability to actively test components makes them indispensable for professional mechanics and serious DIY enthusiasts who need to pinpoint the root cause of vehicle problems accurately. The ability to perform active tests significantly reduces diagnostic time and ensures more effective repairs. Choosing a scanner with bi-directional capabilities empowers users to diagnose and address a wider range of automotive issues.
Bi-directional scanners offer advanced diagnostic capabilities.
