Buell 2007 ULYSSES, Service Manual, Page: 413 / 647

4-64 2007 Buell Ulysses: Fuel System
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TROUBLE CODE 21 4.21
ACTIVE MUFFLER CONTROL
The interactive exhaust system utilizes an actuator valve in
the muffler which is connected to a servo motor via a cable.
The valve position automatically adjusts to enhance engine
performance.
A Code 21 will set if the ECM detects that the output for the
Interactive Muffler Control Actuator is not in agreement with
the feedback circuit.
● Mechanical fault in the actuator, valve or cable.
●
Electrical fault in the actuator circuit.
● Electrical fault in the actuator feedback circuit.
●
Electrical fault in the brake light or horn circuits.
See B.5 INDEX TO WIRING DIAGRAMS .
DIAGNOSTIC NOTES
The reference numbers below correlate with the circled num-
bers on the Code 21 flow charts.
1. Using TEST CONNECTOR KIT (Part No. HD-41404),
attach red probe and patch cord to [164B].
2. Using TEST CONNECTOR KIT (Part No. HD-41404),
use gray male pin probe and patch cord.
Figure 4-42. Fuses and Diodes
39
40
41
42
43
44
33
34
35
36
37
38
21
22
23
24
25
26
28
29
30
31
32
27
Spare
Diode
Bk/Hn/Mflr
Fan
IGN
Acces.
Key Sw
Lights
ECM
Spare
Aux.
Battery
bs0026ax