GxT Ferret 54 ENGINE DIAGNOSTIC CENTER - Manual (Page 51)

SENSORS
The Auxiliary Meter Lead is used for all of these tests, except the Vacuum/Pressure tests.
THROTTLE POSITION SENSOR (TPS)
Press SENSORS, SELECT TPS Test , and press NEXT. This is a computer aided test to check
for skips (glitches) in a position sensor signal sweep. When a position sensor on a throttle or
air flow vane is moved from the rest position to the top, the output voltage should move just
like the position shaft. A dedicated glitch detector operates continuously and is not dependent
upon sample rate.
Connect the Auxiliary Meter Lead to the throttle position sensor output wire. Switch the ignition
key to the ON position. The test screen will appear with a prompt to move the sensor slowly
through its range.
Move TPS slowly but steadily to W.O.T.
0v 2.5v 5v
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Voltage: 3.90 ÛNEXT to clear }'s
Slowly move the sensor shaft through its full range. Using the voltmeter display, check that
the output responds to a typical range of 1 to 4 volts.
}}
0v 2.5v 5v
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Voltage: 3.90 ÛNEXT to clear }'s
The Diagnostic Center detects abrupt voltage changes that an intermittent sensor contact would
cause. If glitches are detected, arrows will appear in place of the prompt, showing the voltage
location of each glitch. Recheck the sensor for intermittent faults near the indicated problem
voltages. The arrows can be cleared by pressing the NEXT key.
AUXILIARY METER
See description in the ELECTRICAL section of this manual.
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