Mode $01 — Request current powertrain diagnostic data
- The purpose of Mode $01 data is to have access to current live powertrain data values.
Mode $02—Request freeze frame information
- The purpose of Mode $02 is to allow access to emissions-related data that is stored at the time the related code was set.
Mode $03—Request emissions-related diagnostic trouble codes
- The purpose of Mode $03 is for the external test equipment (scan tool) to have access to emissions-related Diagnostic Trouble Codes (DTCs) that are stored in emissions-related modules.
Mode $04—Clear/reset emissions-related diagnostic information
- The purpose of Mode $04 is to clear the emissions-related diagnostic information from the modules that have stored this information. This function includes clearing not only the DTCs; but also the freeze-frame data, all stored test data, and it resets all monitors and turns off the check engine light.
Mode $05—Request oxygen sensor monitoring test results
- The purpose of this mode is to allow access to the engine control module’s oxygen sensor monitoring test results. The same information can be obtained by the use of Mode $06. The Mode $05 information is not available on vehicles using the Controller Area Network (CAN) system. For those cars, you’ll need to go directly to Mode $06.
Mode $06—Request on-board monitoring test results for specific monitored systems
- The purpose of Mode $06 is to allow access to the test results for on-board diagnostic monitoring tests of specific components that are both continuously monitored (misfire monitoring) and non-continuously monitored systems. The Mode $06 test information has nothing standard between vehicle makes or models. The only way to understand what you are seeing is to either have a scan tool that defines all of the data for you, or to print out the Mode $06 information from service information then compare the printed data to the scan tool data.
Mode $07 — Request emission-related diagnostic trouble codes detected during current or last completed driving cycle
- The purpose of Mode $07 data is to allow the scan tool to have access to codes that have been stored on the first drive cycle after an ECM reset. This is the “pending codes” selection you see on many scan tool menus.
Mode $08—Request control of on-board system, test or component
- The purpose of the Mode $08 is to allow a scan tool to do bidirectional control of an onboard system or test. Typically, it is currently limited to some evaporative emissions systems and allows the user to seal the system for leak testing.
Mode $09—Request vehicle information
- The purpose of Mode $09 is to allow a scan tool access to the vehicle identification number and calibration numbers from all emissions-related electronic modules.
Mode $0A—Request emissions-related diagnostic trouble codes with permanent status after a clear/reset emission-related diagnostic information service
- The purpose of mode $0A, referred to as Mode 10, is to allow a scan tool to obtain DTCs that are stored as “permanent codes.” These are codes only the module can clear. Even if you’ve made a successful repair and have cleared the codes in Mode $04, these codes will remain in memory until the computer has completed its own system test.