# The history storage / history data Certain events such as performing a transmission oil change, configuring the shift programs or reprogramming actions are stored in a time context in the history storage of the transmission control unit. This data is recorded throughout the entire runtime of a transmission (and never deleted). The history storage is designed as a FIFO memory (First In First Out), data is therefore stored automatically in chronological order. A successive event number is assigned to every event that is entered. In addition, a time stamp is stored in the history storage. This time stamp is composed of a relative time indication and, if provided, an absolute time indication such as the transmission and the vehicle mileage. The history storage can have up to 50 entries. If there is one free location left in the FIFO memory, the event that is signalled will be entered in the first free location. If all memory locations of the history storage are occupied, the oldest event with multiple entries will be deleted. If no multiple entries are provided, the oldest entry will be deleted. Please refer to: The history storage in the ECU report.
| The history storage is available as of transmission software version E300.1-D5.2.0.0.
| Events that are stored in the history storage:
Oil change support has been activated. Oil ageing index has been reset. Oil level trend memory has been cleared. New software (incl. dataset) has been loaded. A new software has been loaded. Dataset parameter has been modified. Modified TIM data has been detected. New TIM data has been downloaded. Shift program configuration has been reset. Shift program configuration has been modified. Adaptation data has been deleted. Service data has been deleted. History storage has been cleared. Event memory has been cleared. ...
| How to clear the history storage:
The history storage records its data throughout the entire transmission runtime and is therefore never cleared. That is why the function to clear the history storage is reserved to the transmission production and development. If you want to clear the history storage, click Service > Reset functions > Clear the history storage. For further information, please see: Reset functions.
| The function of absolute and relative time indications:
Absolute time indications are points in time. Relative time indications are time spans. Absolute time indications describe a point in time such as date or time. "It is 15:00." is an absolute time indication. This information is signalled to the transmission control unit via the CAN bus. If the CAN bus does not provide this data, the history data will only be stored with the relative time indication. Relative time indications describe a time span or the difference between two events such as the occurrence of an event and reading out the history storage. "It takes 15 minutes" is a relative time indication. For further information, please see: Time stamp in the event memory.
| Further topics:
More information on: Report More information on: Service More information on: The history storage in the ECU report More information on: Time stamp in the event memory More information on: CAN More information on: FAQ Up > Higher-level section © by Voith Turbo GmbH & Co. KG send remarks to joachim.ehleiter@voith.com (electronic department) or r.theilacker@voith.com (electronic department)