EXTENSION GP-EXHAUST 1410643 - Caterpillar

Snapshot That is Triggered by a Diagnostic Code
When certain diagnostic codes occur the ECM records many of the status parameters that are available on Cat ET. The ECM records this information for approximately nine seconds before the code occurs and approximately four seconds after the code occurs.Snapshot That is Triggered by the Operator
A snapshot can be triggered by the operator by using the Cruise Control Set/Resume Switch, or by using Cat ET. Use the following procedure in order to trigger the snapshot with the Cruise Control Set/Resume Switch:
Illustration 1 g00627693
(1) OFF position
(2) SET position
(3) RESUME position
Toggle the switch quickly from the OFF position (1) to the SET position (2).
Toggle the switch quickly from the SET position (2) to the RESUME position (3).
Toggle the switch quickly from the RESUME position (3) back to the OFF position (1). Note: All three steps must occur within a one second time period in order to take a snapshot. Performing the steps in the reverse order also triggers a snapshot.On Cat ET, the snapshot can be triggered from the Snapshot Recorder Tool. Refer to the instructions on the screen or the system's documentation for help.Snapshot That is Triggered by a Quick Stop
A snapshot can also be recorded for a Quick Stop event if the customer parameter is programmed. The ECM stores the number of occurrences of the Quick Stop event and a snapshot of the latest occurrence.One data record is kept for the most recent Quick Stop event. The previous record is replaced by the most recent record.Each Quick Stop record contains 60 frames of information. Frame 45 is the Quick Stop event. The record contains 44 frames before the Quick Stop event and 15 frames after the Quick Stop event. Each frame is separated by one second. Each frame of the Quick Stop record stores the following data:
Engine RPM
Throttle Position
Clutch Switch
Vehicle Speed
Cruise Status
Brake SwitchUse of Snapshot Data
Use snapshot data only to help determine engine/vehicle operating conditions when an intermittent problem occurs. If an intermittent diagnostic code is causing problems, use the snapshot data. Snapshot data can be used to determine whether the problem occurs under specific circumstances. The following list contains examples of specific circumstances:
Engine rpm
Range of vehicle speeds
Range of coolant temperaturesUse the snapshot data in order to determine the operating conditions that were present during the event. Attempt to duplicate the conditions in order to get the code to recur.Do not replace electronic components only because of snapshot data. If too much emphasis is put on snapshot data, the result could be a misdiagnosed root cause. Also when snapshot data that is triggered by a diagnostic code is being viewed, the ECM sets a sensor value with an active diagnostic code to a default value when the code is active. This is the reason that the sensor value suddenly jumps to a specific value at the trigger point and the sensor value remains at the specific value for the rest of the snapshot frames.