HOW TO USE ON-BOARD DIAGNOSTICS - CONTINUED
DIAGNOSTIC CODES - CONTINUED
N OT E
The "More Info" button is only enabled when diagnostic procedures are available. Buttons in the Active
Diagnostic Codes screen are "More Info" and "Print".
Logged Diagnostic Codes. When an ECM generates a diagnostic code, it logs that code in permanent memory
using an internal diagnostic clock.
The ECM records the hour of first occurrence, the hour of last occurrence, and the total number of occur-
rences using its internal diagnostic clock.
A screen is provided in ET for displaying logged diagnostic codes. Logged diagnostic information
includes a CID, a FMI, and a text description of the problem.
(a) Purpose. The Logged Diagnostic Codes function provides a list of diagnostic codes logged by each
ECM. These codes are similar to active diagnostic codes except they are logged over time.
(b) Accessing. To run the Logged Diagnostic Codes function, select Logged Diagnostic Codes from the
(c) Screen Layout. The Logged Diagnostic Codes display area has five columns: Code, Description, Occ.,
First, and Last. The code numbers that appear are used to identify specific diagnostic codes. The
Description column informs you of the problem that is occurring. The Occ. (occurrences) column
shows the number of times the problem occurred. The First and Last columns indicate the first and last
ECM hour that the problem occurred.
The list of codes is grouped according to the ECM from which they were retrieved, and they appear
ordered chronologically by the most recent ECM hour of last occurrence. The ECM names appear as
subtitles in the list. On the same line as the ECM subtitle, the number of ECM diagnostic clock hours
is displayed. These hours represent the time that the ECM has been connected and running.
When the Include All ECMs check box is checked, logged codes from all available ECMs are
retrieved and displayed. When there is a single ECM on the data link, this check box is disabled. The
buttons available in the Logged Diagnostic Codes screen are: Clear, More Info, and Print.
This information is a valuable indicator for troubleshooting intermittent problems. Any logged diagnostic
codes will automatically be deleted if no additional occurrences are recorded in 150 hours. Some diagnos-
tic codes may be easily triggered. Some diagnostic codes may log occurrences that did not result in com-
plaints. The most likely cause of any intermittent problem is a faulty connection or damaged wiring. The
next likely cause is a component failure. The least likely cause is an ECM failure. Diagnostic codes that
are logged repeatedly may indicate a problem that needs special investigation.
Active Event Codes.
Purpose. The Active Events Code function provides information about events currently occurring. These
codes are similar to active diagnostic codes except the event code represents the symptom on an opera-
tional level. These codes indicate to the manager or technician how the machine or equipment can be oper-
Accessing. To run the Active Events Code function, select Events from the Diagnostics menu, then select
Active Events Code from the sub-menu. You may have to customize the tool bar to view Active Event
Screen Layout. The Active Event Codes display area has two columns: Code and Description. The code
numbers that appear in the Code column are used to identify the events. The Description column describes
the event that is occurring.