What is Mode 6?

The majority of OBD2 scanners have nine standard modes, and each mode corresponds to different data sets. OBD2 is built within vehicle computers to allow external equipment, namely an OBD2 scanner, to ask for specific data on the current vehicle systems' status.

Mode $06 retrieves test results for emission-related powertrain components and systems that are not continuously monitored. It can also be used as an alternative method to Mode $05 for obtaining oxygen sensor test results. This mode does not command the vehicle's computer to perform the tests. It simply retrieves results from the most recently performed tests from the computer's memory. The tests available are determined by the vehicle manufacturer. They can include any or all of the following monitored systems and components, as well as other manufacturer-defined test results. The following systems are tested under Mode $06:

Oil Life
Oil Level
Battery Status
Transmission Fluid Temp
Tire Pressure
Oxygen Sensors
Catalytic Converters
Exhaust Gas Recirculation System
Evaporative Emissions System
Purge Flow Monitor
Oxygen Sensor Heaters
Heated Catalytic Converters
Secondary Air System
Fuel System
Misfire Monitor

Mode $06 retrieves scanned results from the systems listed above. With this mode, mechanics can simply plug the OBD2 scan tool into the DLC port and use the results to determine if your vehicle will pass emissions testing.

Is Mode $06 Useful?

Mode $06 is useful for vehicle users, owners, and mechanics by displaying system results that determine if a system is either failing, low performing, or in need of an inspection. This mode is very useful for checking failing systems that do not cause the check engine light to turn on. With this mode, it will be easier to detect failures that do not turn on the check engine light on your dashboard.

Mode $06 Constraints

With Mode $06, it can be difficult to pinpoint a specific failure within the system. Component testing varies from vehicle make, model, and year of manufacturing. Some vehicles have more testing components than other vehicle models.

If you are unable to determine the specific component that Mode 6 retrieves, the data will not be of any use and will just result in a failed emission test. Regarding component testing, some vehicles may run different tests for the same components and show different results. Other vehicles use a Voltage Reading, and some use Current Reading.

How to Use Mode $06 Effectively

Mode 6 data may be broad, but it is still very useful in diagnosing a vehicle's issues or problems. This mode can be the starting point for diagnosing or troubleshooting problems with your vehicle.

Mode 6 Line of Data Code Tags

Since 2003, a new communication system, namely the Controller Area Network bus (CAN), has been installed on cars. Since then, two indication tags of the Mode $06 line of data have been identified:

Monitor Identification (MID) - a code tag indication for monitoring tests. It is also called the Test Identification (TID) for cars manufactured before 2003. MID has been the standard identification since 2003.
Component Identification (CID) - a code tag identification for tested sensors and components.

Reference Chart

A reference chart is needed from your vehicle manufacturer to identify the component or system failure that the line of code refers to and the specific value that is acceptable or that works for your vehicle's system. The numbers indicated in the Mode $06 results can only be considered failing or within the acceptable range if your manufacturer's reference chart specifies it.

How to find a Vehicle's Reference Chart?

Mode 6 varies according to the Vehicle's make, model, and year of manufacture. To access your Vehicle's reference chart, you can contact your manufacturer or find it on their respective online websites.