Buell 2002 S3T, Service Manual

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2002 Buell S3T: Fuel System 4-5
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CHECKING FOR TROUBLE CODES 4.4
CHECK ENGINE LAMP
To diagnose system problems, start by observing the behav-
ior of the check engine lamp.
NOTE
●
See Figure 4-4. All references to “Key ON” or “Ignition
Switch ON” require that the ignition key be in the IGN
position and the engine stop switch be set to RUN.
●
If the check engine lamp is not illuminated at Key ON or if
it fails to turn OFF after the initial four second period,
then a problem exists in the lamp circuit. See
4.10
CHECK ENGINE LAMP NOT ILLUMINATED AT KEY
ON
or 4.11 CHECK ENGINE LAMP ON CONTINU-
OUSLY for more information.
1. When the ignition switch is turned ON after being OFF
for 10 seconds or more, the check engine lamp will illu-
minate for approximately four seconds and then turn off.
2. See Figure 4-5. After lamp turns off after being illumi-
nated for the first four second period, one of three situa-
tions may occur.
a. The lamp remains off. This indicates there are no
current fault conditions or stored functional trouble
codes currently detected by the ECM.
b. The lamp stays off for only four seconds and then
comes back on for an eight second period. This indi-
cates a functional error code is stored, but no cur-
rent trouble code exists.
c. If the lamp remains on beyond the eight second
period, then a current trouble code exists.
3. See CODE TYPES for a complete description of trouble
code formats.
NOTE
Trouble codes relating to the fuel injectors or the ignition coil
can only be fully diagnosed during actuation. For example, a
problem with the ignition coil will be considered a current fault
even after the problem is corrected, since the ECM will not
know of its resolution until after the coil is exercised by vehi-
cle start sequence. In this manner, there may sometimes be
a false indication of the current trouble code.
Figure 4-4. Ignition Key Switch
1. Ignition OFF
2. Marker Lights ON
3. Ignition ON
1
b0466xox
3
2
Figure 4-5. Check Engine Lamp Operation
ON
OFF
ON
OFF
ON
OFF
Key ON
Key ON
Key ON
A
B
C
Lamp OFF: no current trouble code*
Lamp remains ON: current trouble code*
Lamp OFF
Lamp ON 8 seconds:
functional error**
4 Sec.
4 Sec.
4 Sec.
4 Sec.
4 Sec.
8 Sec.
* Historic trouble code may exist
** Trouble codes 53-55, ECM failure & 56,
crankshaft/camshaft timing