
ON
A
B
C
ON
ON
OFF
OFF
OFF
Key On
Key On
Key On
Lamp OFF: No Current or Historic DTCs
Lamp OFF
Lamp ON 8 Seconds:
Only Historic DTCs Exist
Lamp Remains ON: Current DTC*
* Historic DTCs May Also Exist
4 Sec.
4 Sec.
4 Sec.
4 Sec.
8 Sec.
4 Sec.
ed01550
Figure 2-5. Check Engine Lamp Operation
CODE TYPES
TOOL NAME
PART NUMBER
DIGITAL TECHNICIAN
HD-44750
There are two types of trouble codes: current and historic.
Certain codes are also called functional codes. Historic codes
can be read using the check engine lamp diagnostics.
All trouble codes reside in the memory of the ECM unit the
code is cleared by DIGITAL TECHNICIAN (Part No. HD-44750)
or a total of 50 trips has elapsed. A trip consists of a start and
run cycle lasting at least 30 seconds. After the 50 trip retention
period, the trouble code is automatically erased from memory
providing that no subsequent faults of the same type are
detected in that period.
NOTE
Trouble codes relating to the fuel injectors or the ignition coils
can only be fully diagnosed during actuation. For example, a
problem with the ignition coils will be considered a current fault
even after the problem is corrected, since the ECM will not
know of its resolution until after the coils are activated by
vehicle start sequence. In this manner, there may sometimes
be a false indication of the current trouble code.
Current
Current trouble codes are those which are presently disrupt
motorcycle operation. See the appropriate flow charts for
solutions.
Historic
If a particular problem happens to resolve itself, the active
status problem is dropped and it becomes a historic fault rather
than a current fault.
Historic trouble codes are stored for a length of time to assist
in the diagnosis of intermittent faults. The check engine lamp
will not turn on during normal operation if only historic codes
are present.
It is important to note that historic trouble codes may also be
present whenever the system indicates the existence of a
current fault. See
2.4 CHECKING FOR TROUBLE CODES
if
multiple trouble codes are found.
RETRIEVING TROUBLE CODES
TOOL NAME
PART NUMBER
DIGITAL TECHNICIAN
HD-44750
The fuel injection system provides two levels of diagnostics.
•
The most sophisticated mode employs using a computer
based diagnostic package called DIGITAL TECHNI-
CIAN (Part No. HD-44750).
•
The other mode requires using the check engine lamp.
See
2.5 CHECK ENGINE LAMP DIAGNOSTICS
for more
information.
MULTIPLE TROUBLE CODES
The throttle position and bank angle sensors are connected to
separate lines (5V REF).
Also, the ECM, fuel pump, fuel injectors and ignition coils all
r12 volts from the ignition relay. If this line should go
to ground the ignition fuse will open.
Always start with the trouble code having the highest priority.
Refer to
CHECK ENGINE LAMP FLASHES
In addition to alerting the rider to trouble codes, the check
engine lamp will flash during operation to warn of potentially
damaging temperature. While this condition is in effect, the
ECM will reduce engine power to assist in cooling the engine
2008 Buell XB Diagnostics: Engine Management 2-7
Summary of Contents for 2008 XB SERIES
Page 1: ...2008 Buell XB Models Electrical Diagnostics Manual 99493 08Y 2007 Buell Motorcycle Company ...
Page 4: ...Blank Text Here ...
Page 6: ...NOTES ...
Page 14: ...NOTES ...
Page 50: ...NOTES ...
Page 72: ...ed01568 Figure 2 16 Checking for Leaks 2 22 2008 Buell XB Diagnostics Engine Management ...
Page 202: ...NOTES ...
Page 224: ...A 22 2008 Buell XB Diagnostics Appendix A Connector Repair NOTES ...
Page 225: ...SUBJECT PAGE NO B 1 CONNECTORS B 1 B 2 WIRING DIAGRAMS B 3 APPENDIX B WIRING DIAGRAMS ...
Page 226: ...NOTES ...
Page 232: ...Figure B 2 Figure B 2 Main Harness Ulysses and Lightning Main Harness Ulysses and Lightning ...
Page 234: ...Figure B 3 Figure B 3 Main Harness Firebolt Main Harness Firebolt ...
Page 240: ...Figure B 6 Figure B 6 Lighting Circuit Firebolt Lighting Circuit Firebolt ...
Page 242: ...Figure B 7 Figure B 7 Component Circuits All Models Component Circuits All Models ...
Page 248: ...Figure B 10 Figure B 10 Starting Circuit Firebolt Starting Circuit Firebolt ...
Page 250: ...Figure B 11 Figure B 11 Charging Circuits All Models Charging Circuits All Models ...
Page 266: ...B 40 2008 Buell XB Diagnostics Appendix B Wiring Diagrams NOTES ...
Page 268: ...NOTES ...
Page 272: ...C 4 2008 Buell XB Diagnostics Appendix C Conversions NOTES ...
Page 273: ...SUBJECT PAGE NO D 1 GLOSSARY D 1 APPENDIX D GLOSSARY ...
Page 274: ...NOTES ...
Page 278: ...D 4 2008 Buell XB Diagnostics Appendix D Glossary NOTES ...
Page 282: ...IV TOOLS NOTES ...
Page 284: ...VI TORQUE VALUES NOTES ...
Page 287: ...INSIDE BACK COVER GOES HERE ...
Page 288: ...OUTSIDE BACK COVER GOES HERE ...