
2.24
DTC P0506 (34), P0507 (34), P0511 (34)
GENERAL
TOOL NAME
PART NUMBER
DIGITAL TECHNICIAN
HD-44750
IAC Operation
The ECM controls engine idle speed by moving the Idle Air
Control (IAC) motor to open or close a passage around the
throttle plate. It does this by sending voltage pulses to the
proper motor winding of the IAC motor. This causes the pintle
to move in or out of the IAC motor a given distance for each
pulse received.
•
To increase idle speed, the ECM retracts the pintle,
allowing more air to flow through the throttle body.
•
To decrease idle seed, the ECM extends the pintle,
allowing less air to flow through the throttle body.
The IAC motor position is measured in steps. This can only be
done by using a computer based diagnostic package called
DIGITAL TECHNICIAN (Part No. HD-44750).
•
A high number of steps represents a retracted pintle and
open passage around throttle plate. This correlates with
an increase in the amount of air flowing through the throttle
body.
•
Five steps represents a fully extend pintle. A five reading
indicates an abnormal condition in which the pintle has
been fully extended and has consequently closed the
passage around the throttle plate
Each time the ignition switch is turned ON, the ECM resets the
IAC motor by sending enough pulses to extend the pintle and
effectively close the throttle body. The fully extended value is
the ECM reference point. A given number of steps are then
calculated by the ECM for use in setting the proper idle speed
and IAC position.
Table 2-44. Code Description
DESCRIPTION
CHECK
ENGINE
LAMP CODE
DTC
Idle Air Control (IAC) system
RPM higher than expected
34
P0506
Idle Air Control (IAC) system
RPM lower than expected
34
P0507
Idle Air Control (IAC) circuit
34
P0511
ed02020
Figure 2-64. IAC Test Lamp (Part No. HD-41199-3)
ed01302
Figure 2-65. IAC Motor Connector
ed01301
Figure 2-66. IAC Motor Pintle Air Inlet
2-84 2008 Buell XB Diagnostics: Engine Management
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 ...