Professional Training Series
Mode 6 Scan Diagnostics
OBD II standards specify 10 modes of operation for the ECM/PCM. Mode 06 is one of these modes. Manufacturers are required to monitor the emission systems on modern vehicles to ensure they are performing properly. This is done by running a series of tests or Monitors on each system. Some of these tests are Continuous and are always monitoring a system for failures. While others are Non-Continuous and only run once per drive cycle.
The test results for these Non-Continuous Monitors are stored in Mode 06. When one of these monitors fails a DTC will be stored in either Mode 03 or Mode 07, a Freeze Frame will be stored in Mode 02 and the MIL may be illuminated. In some cases the DTC may also be stored in Mode 10. The test results stored in Mode 06 can be helpful in diagnosing the cause of the fault. But these tests only fail if the results are outside pre-set parameters. A system can be close to failing but not set a DTC. Mode 06 data will help you find faults in those systems before they fail. Mode 06 can also be used to verify a repair. Running the Monitor and checking the test results after the repair will help verify there are no other issues with the system, before you release the vehicle to the customer.
In this class we will outline what each of the 10 modes does. We will show examples of Mode 06 using different scan tools and where to access the information you need to start using it. We will also look at the difference between Mode 06 on vehicles with and without CAN protocol.