Buell 2003XB9S - Tachometer Performance Check

7-58 2003 Buell XB9S: Electrical
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TACHOMETER PERFORMANCE CHECK 7.20
GENERAL
NOTE
Tachometer performance check can also be performed using
DIGITAL TECHNICIAN (Part No. HD-44750).
See Figure 7-65. Use the SPEEDOMETER TESTER (Part
No. HD-41354) for tachometer diagnostics. These diagnostics
may include:
● Checking tachometer operation.
● Testing tachometer needle sweeping action.
The tester can be connected to the vehicle’s cam position
sensor connector. This connection introduces a signal to the
ignition module that simulates the signal from the cam posi-
tion sensor. The ignition module will use this simulated signal
to open and close circuits to fire the spark plugs. This allows
you to simulate the engine running and therefore generate
tachometer readings.
TESTING
Operation Test
NOTE
For information on the correct routing of speedometer sensor
wiring see 7.25 SPROCKET COVER WIRING.
1. See Figure 7-68. Locate the 3-place cam position con-
nector [14] under the sprocket cover. See 2.31
SPROCKET COVER.
2. See Figure 7-69. Connect the speedometer tester to the
cam position sensor Deutsch socket housing using test
harness. See Speedometer Sensor Test under 7.19
SPEEDOMETER PERFORMANCE CHECK for more
information on test harness.
3. Convert the desired test RPM to a tester frequency in
Hertz. Several conversions are listed in Tabl e 7-17.
a. Select a desired tachometer reading for testing. This
example will use 2000 RPM.
b. Divide the desired tachometer reading by 60. For
example, 2000/60=33.3.
NOTE
All tachometer accuracy tolerances were taken at 68 °-77 ° F
(20-25 ° C).
4. Enter the result (33.3 for 2000 RPM) into the speedome-
ter tester.
a. The tachometer should respond by moving its nee-
dle to the desired RPM.
b. Test the tachometer at several different RPM read-
ings to verify proper operation.
Figure 7-68. Cam Position Sensor Connector
Table 7-17. Tachometer Accuracy
Tolerances and Conversions
READING
2000
RPM
4000
RPM
6000
RPM
7500
RPM
Tole rance
(+/- RPM)
100 120 210 320
Conversion
factor
33.3 66.7 100 125
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