Freeze Frame and Failure Records

Storing Freeze Frame And Failure Record Data:

Freeze Frame is an element of the Diagnostic Management System that stores various vehicle information in the PCM memory at the moment an emissions-related fault occurs that commands the MIL On. Freeze Frame data is useful in identifying the cause of an emission-related fault. Freeze Frame data is accessed by the scan tool and can be saved with the Capture Data feature. Refer to Storing And Erasing the Freeze Frame Data in Powertrain Control Module Diagnosis for more detailed information.

The PCM can store one Freeze Frame and save the recorded data of three additional Freeze Frames as Failure Records. Therefore the PCM can store up to 4 frames of Freeze Frame and Failure Record data. The 1st frame stores data of the fault that was detected first. The data from the 1st detected fault is also stored in the 2nd frame as a Failure Record. The Failure Record data stored in the 2nd frame is permanent, and will not change when a new fault is detected. The 1st frame of Freeze Frame data will remain unchanged unless a fault of a higher priority occurs. A misfire fault (DTC P0300-P0304) or a fuel trim fault (DTC P0171 and P0172) will replace the data in the 1st frame of Freeze Frame data because these DTCs have a higher priority under OBD 2 rules. The 2nd through 4th frames of Failure Records will store fault data in the order that the faults were detected regardless of the fault's priority. Utilizing the 4 frames of Freeze Frame and Failure Record data can provide information on the order in which the faults were first detected. The following table indicates how Freeze Frame and Failure Record data is stored when two or more faults are detected.