20593218 Volvo.Penta Control unit, EDC iv

Active Diagnostic Codes
An Active diagnostic code represents a problem with the electronic control system that should be investigated and corrected as soon as possible.When an Active diagnostic code is generated, a display module such as VIMS may produce an audible or visible warning indicator to alert the operator. If the condition generating the diagnostic occurs only for a brief moment, the message will disappear and the diagnostic code will be Logged in the ECM memory.Logged Diagnostic Codes
When the ECM generates a diagnostic code, it usually logs the code in permanent memory within the ECM. The ECM has an internal diagnostic clock and will record the hour of the first occurrence, the hour of the last occurrence and the number of occurrences of the code. Knowing when and how often the code was generated can be helpful when troubleshooting intermittent problems.An Electronic Service Tool can retrieve and delete Logged codes. Any Logged diagnostic codes will automatically be deleted if no additional occurrences are recorded in 100 hours.When investigating logged diagnostic codes, keep in mind the following information.* Some diagnostic codes may be easily triggered and will log occurrences that did not result in operator complaints. If the time the code was logged does not correlate to a complaint, there may be nothing to repair.* The most likely cause of an intermittent problem is a faulty connection or damaged wiring. Next likely is a component failure (sensor or switch). Least likely is failure of the ECM itself.* Diagnostic codes that are logged repeatedly may indicate a problem that needs special investigation.To troubleshoot a Logged diagnostic code, refer to the Quick Reference Sheet For Diagnostic Codes in this section. The code number will direct you to a procedure in Section 5: Functional Tests. If the symptoms continue, use the proper procedure for troubleshooting the symptoms that have been experienced by the operator. Refer to Section 3: Troubleshooting Without a Diagnostic Code. Always clear logged diagnostic codes after investigating and correcting the problem which generated the code.
Figure 4.1 - Reference: Output Voltage from an Analog Temperature Sensor. The diagram shown is for reference only and should not be used to troubleshoot Analog Sensors.Logged Events
The ECM can log events. Events refer to engine operating conditions such as low oil pressure or high coolant temperature. Logged events do not indicate an electronic system problem, but may indicate an engine system problem. The example diagram shown indicates the output voltage from an Analog Temperature Sensor and how the ECM responds to the output voltage. The diagram shown is only an example and should not be used to troubleshoot any particular analog sensor.Programmable Shutdown, Warnings and Derates
On some applications, shutdowns, warnings and derates are programmable. The Electronic Service Tool can be used to turn these features ON and OFF. When the features are turned ON, the display will appear on an electronic monitoring system display module (i.e. VIMS) and an Event will also be logged in the ECM. When a warning is turned OFF, it will not appear on the display module, but an Event will still be logged. Refer to Section 2 for additional information.Using ECAP to Display Active or Logged Diagnostic Codes
1. Connect an ECAP and Communication Adapter Tool to the Service Tool connector.2. Turn the keyswitch to the ON position, engine OFF.3. Select the Display Diagnostics/Events option from the menu.4. Each diagnostic code CID and FMI are listed on the left and followed by a text description.5. The ECAP also displays number of times the diagnostic code occurs and the engine hours at the first and last occurrence of the diagnostic code.6. The diagnostic status display is located on the far right of the display window. (a) The ACTIVE bar indicates the diagnostic is occurring.(b) No text present, as shown on the first two diagnostics, indicates that two codes are logged but are not active.
Figure 4.2 - ECAP Diagnostic Display ScreenUsing ET to Display Active Diagnostic Codes
1. Connect ET and the Communication Adapter Tool to the Service Tool connector.2. Turn the keyswitch to the ON position, engine OFF.3. Select the Display Active Diagnostics option from the Tools Menu.4. Each Diagnostic Code CID and FMI are listed on the left followed by a text description
Figure 4.3 - ET Active Diagnostic Code ScreenUsing ET to Display Logged Diagnostic Codes
1. Connect ET and the Communication Adapter Tool to the Service Tool connector.2. Turn the keyswitch to the ON position, engine OFF.3. Select the Display Logged Diagnostics option from the Tools Menu.4. Each Diagnostic Code CID and FMI are listed on the left followed by a text description.
Figure 4.4 - ET Logged Diagnostic Code ScreenUsing VIMS to Display Active or Logged Diagnostic Codes:
VIMS receives engine operating parameter and diagnostic / event code information from the ECM over the CAT Data Link and alerts the operator of abnormal conditions that exist. Information may be viewed on the VIMS Message Display by entering the following commands into the VIMS Keypad:1. Show Acknowledged Events: Type in EACK (3225) on the VIMS Keypad. This will show only active events that have been acknowledged but not corrected.2. Show Event List Contents: Type ELIST (35478) on the VIMS Keypad. This will show the event list in abbreviated form. Event list entries are displayed on a last in/first out basis. Use the arrow keys to scroll through the list. The message "BOTTOM OF LIST" is displayed when the first event in the list is reached.Pressing the <F1> key while a fault is displayed will show the event MID, CID, and FMI on the second line of the VIMS Message Display. Refer to the VIMS Service Manual (SENR6059) for more detailed information.
Figure 4.5 - VIMS SystemDiagnostic Terminology
Module Identifier (MID)Two or three digit code which is assigned to each module or control system. Component Identifier (CID)Two or three digit code which is assigned to each component or system.Failure Mode Identifier (FMI)Type of failure the component experienced (adopted from SAE standard practice J1587 diagnostics). Active CodeThe MID, CID and FMI can be sent through the