Diagnostics - Buell 2008 XB SERIES Electrical Diagnostics Manual

DIAGNOSTICS

PART NUMBER
B-48115 BREAKOUT BOX
HD-41404-B HARNESS CONNECTOR TEST KIT
Diagnostic Tips
Engine idle speed can be adversely affected by the following:
A loss of idle speed control does not necessarily imply the
IAC motor or wiring has failed. It can be caused by a
number of conditions such as an intake air leak, improperly
adjusted throttle stop (factory set) or a misfiring cylinder.
Leaking injectors will cause fuel imbalance and poor idle
quality due to different air/fuel ratios in each cylinder, To
check for leaky injectors , first remove the air cleaner. See
Air Cleaner in the appropriate Buell Service Manual. Turn
key ON for 2 seconds five consecutive times. Replace the
fuel injector if there is any evidence of raw fuel in bores.
See Fuel Injectors in the appropriate Buell Service Manual.
To confirm IAC function, disconnect fuel pump. Turn
engine stop and ignition switch on and listen for IAC
movement (clicking or humming noise) for a few seconds
after the ignition switch is turned on.
Vacuum leaks. To check for vacuum, see Intake Leak Test
in the appropriate Buell Service Manual.
Contaminated fuel.
Excessive oil in crankcase (oil sumping).
Throttle Position (TP) sensor reading of greater than 5%
(possible throttle cable misadjustment) or battery voltage
reading of less than 9 volts will disable idle speed control.
[11A]
em00061
ECM
J1
[11A]
(GY)
DLA 2B
DLA 2A
DLA 1B
DLA 1A
J2
[10A]
(BK)
[10A]
NO. DESCRIPTION
[11] ECM (GY)
[87] Idle Air Control (IAC) motor
TOOL NAME
[11B]
20 20 BK/PK
21 21 BE/GN
22 22 BN/R
BK/O
23 23
[10B]
Figure 2-67. IAC Motor Circuit
Table 2-45. Wire Harness Connectors
MODEL
Firebolt
Ulysses, Lightning
All
Diagnostic Notes
Each reference number below correlates to a circled number
on the flow chart(s).
1. When the ignition is keyed ON, the IAC motor pintle
extends and then retracts to a fixed position for increased
airflow and idle speed during the engine start sequence.
This ON reset procedure takes 2 seconds to perform.
2. Test lamp behavior may follow two patterns. The color of
the lights is not relevant to IAC motor operation.
a. Normal behavior: At ignition switch ON, test lights will
alternately flash to confirm Electronic Control Module
(ECM) signals.
b. Problem indicated: One or more lights fail to illuminate
during ignition switch ON/OFF cycle.
There is a remote possibility that one of the circuits is shorted
to voltage which could have been indicated by a steady light.
Disconnect the ECM and turn the ignition switch ON. Probe
terminals to check for this condition.
3. Connect BREAKOUT BOX (Part No. B-48115) to main
wire harness only leaving ECM disconnected. See
2.6 BREAKOUT BOX.
4. Use HARNESS CONNECTOR TEST KIT (Part No. HD-
41404-B), purple pin probe and patch cord.
5. Repair faulty ECM connection or replace ECM. If ECM
requires replacement, see ECM in the appropriate Buell
Service Manual.
2
3
4
1
[87B]
TYPE
34-place Amp (Tyco)
4-place Delphi
2008 Buell XB Diagnostics: Engine Management 2-85
NOTE
Idle Air
2
Control
3
(IAC) Motor
4
1
[87A]
LOCATION
In fairing
Under seat
Beneath air cleaner base-
plate