Tools Required
J 42598 Vehicle Data Recorder
Snapshot is a recording of the parameters of a control module while the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle condition is current. This allows you to concentrate on making the condition recur, rather than trying to view all the data in anticipation of the fault. The snapshot contains information around a trigger point that you have determined.
There are many different scan tools that have varying functions. For example, the Tech 2 Scan Tool can also graph parameters separately or in combinations of parameters for comparison. Only a single data list may be recorded in each snapshot. It can trigger a Snapshot manually at the time the symptom is noticed, or be set up in advance to trigger when a DTC sets. The Tech 2 Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a first-in, first-out basis. If a third snapshot is taken, the first snapshot stored in the memory will be lost.
Snapshots can be 1 of 2 types:
| • | Snapshot--taken from the Snapshot menu choice |
| • | Quick Snapshot--taken from the Data Display soft key choice, does not contain DTC information |
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1,200 frames of information. Because the snapshot is recorded onto the memory card, snapshots are not lost if the Tech 2 Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis. The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected values by plotting 3 parameters at a time. The data will be displayed both graphically and numerically showing the minimum and maximum values for all frames captured. This is helpful, especially if the fault occurs only once and does not set a DTC.
Vehicle Data Recorder
The J 42598 is connected to the data link connector (DLC) and sent with the customer. The J 42598 captures data for later retrieval and analysis by the technician. Refer to the vehicle data recorder user instructions for more information.
