Reading Diagnostic Trouble Codes: History

This selection will display only DTCs that are stored in the PCM/ECM's history memory. It will not display type B DTCs that have not requested the Malfunction Indicator Lamp (MIL). It will display all type A and B DTCs that have requested the MIL and have failed within the last 40 consecutive warm up cycles. In addition, it will display all type C and type D DTCs that have failed within the last 40 consecutive warm up cycles.

This message display indicates that the DTC has been stored in memory as a valid fault. A DTC displayed as a History fault may not mean that the fault is no longer present. The history description means that all the conditions necessary for reporting a fault have been met (maybe even currently), and the information was stored in the control module memory.