853814 Mercury FUSE

ACTIVE Diagnostic Codes
The Functional Tests are designed to establish whether a component and related parts are working correctly and if not, to pinpoint the faulty component.These tests may also be used for basic health checks, to determine if problems exist, or as a guide to check for intermittent problems.Diagnostic codes are used by the 3176B system to alert the machine operator of a problem and indicate to the service technician the nature of the problem. Some codes are used only to record an event, and do not indicate problems.Example ECAP Screen: Display ACTIVE Diagnostic Messages An ACTIVE diagnostic code represents a problem that should be investigated and corrected AS SOON AS POSSIBLE. Repairing the cause of an ACTIVE diagnostic code will cause the code to be cleared from the ACTIVE Diagnostic Code Status screen.When an ACTIVE diagnostic code is generated, the Check Engine/Diagnostic Lamp will be ON and remain ON, blinking every five seconds. If the condition generating the condition occurs only for a brief moment, the lamp will be OFF after five seconds and the diagnostic code will be LOGGED. Not all diagnostic codes will cause the Check Engine/Diagnostic Lamp to be ON, nor will they flash out using the Lamp Flash Switch as described. After a problem has been investigated or corrected, the related diagnostic code should be cleared from memory.ACTIVE codes may be viewed using an Electronic Service Tool and may also be viewed using the Check Engine/Diagnostic Lamp and Lamp Flash Switch. Some troubleshooting procedures, such as disconnection of a sensor may cause additional diagnostic codes. Make sure all diagnostic codes are noted prior to the start of the troubleshooting procedure to avoid confusion.Using The Electronic Service Tool To Display ACTIVE Codes
A. With keyswitch in the OFF position, connect an Electronic Service Tool to the 3176B system via the Dash Data Link Connector.B. Turn the keyswitch to the ON position (engine does not need to be started to view codes).C. Refer to the Operating Manual and Special Instructions for the Electronic Service Tool to read the code(s). The display menu will direct you to the proper screen to display diagnostic messages similar to the example below.LOGGED Diagnostic Codes
When an ECM records a diagnostic code, it usually logs the code in permanent memory within the ECM. The time the code occurred (in hours on the internal ECM diagnostic clock) is logged along with the code. The logged codes can then be later retrieved or erased using an Electronic Service Tool. They can be a valuable indicator when troubleshooting intermittent problems.When investigating Logged diagnostic codes, keep the following in mind.* Some codes may be sensitive, and may 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 fix.* The most likely cause of an intermittent problem is connections or damaged wiring. Next likely is the component (sensor or injector, for instance). Least likely is the ECM.* Some codes represent events, not failures. An example of a Logged Event is a 190-00 (35) Engine Overspeed Warning. A Diagnostic Event Code does not usually indicate an electronic failure.* The ECM will automatically delete any logged diagnostic code after 100 ECM clock hours. Some troubleshooting procedures, such as disconnection of a sensor may cause diagnostic codes. Make sure all diagnostic codes are noted prior to the start of the troubleshooting procedure to avoid confusion.To troubleshoot a logged diagnostic code, refer to the procedure in this manual for troubleshooting the specific code first (Troubleshooting With A Diagnostic Code). If symptoms continue, use the procedure for troubleshooting symptoms. Refer to Section 3: Troubleshooting Without A Diagnostic Code.Using The Electronic Service Tool To Display Logged Codes
With keyswitch in the ON position or engine running, follow the directions of the Operating Manual and Special Instructions for the Electronic Service Tool to view the codes. The Electronic Service Tool menu will direct you to the proper screen to display logged diagnostic messages.Using The Electronic Service Tool To Clear Logged Codes
Follow directions in the Operating Manual and Special Instructions for the Electronic Service Tool to clear logged codes. The Electronic Service Tool menu will direct you to the proper screen to clear logged diagnostic codes, similar to the example below.