Freeze Frame Data

When a freeze frame event is triggered by an emissions related Diagnostic Trouble Code (DTC), the Powertrain Control Module (PCM) stores various vehicle information as it existed the moment the malfunction occurred. The DTC number along with the engine data can be useful in aiding a technician in locating the cause of the malfunction. Once the data from the 1st trip DTC occurrence is stored in the freeze frame memory, it will remain there even when the fault occurs again (2nd trip) and the MIL is illuminated. Freeze frame data will not be displayed after 40 drive cycles have occurred without a fault. Data can be stored in freeze frame for only one event, however, the PCM will prioritize what data it will store.

Example:
An EGR malfunction (priority 2) was detected during the 1st trip and the freeze frame data stored. After that, a misfire DTC occurs (priority 1) in another trip; the misfire data will replace the EGR data stored in the freeze frame memory, except after a misfire or fuel injection system DTC, which will not be cleared until 80 consecutive drive cycles have occurred without a fault.