TM 9-2320-387-24-l
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1 2-47. VEHICLE TESTING
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a. General. To troubleshoot a vehicle problem, the technician can use the STE/ICE-R (vehicle test meter
and transducers) and the vehicle test card.
b. Data Entry Tests. For information regarding Data Entry, Cylinder Entry, VID Entry, and Data
Display Tests, refer to TM 9-4910-571-12&P.
c. Offset Tests. The STEACE-R VTM performs a test by setting the TEST select switches to the test
number and pressing the TEST button. For some tests, an offset test is required before the test itself can be
performed. This is done by selecting the number of the desired test and holding the TEST button down for
several seconds;
The offset test nullities characteristic differences in the VTM, test leads, and transducers. It zeros the
meter. Once the offset is performed, the VTM automatically corrects for the offset before displaying
measured values. The displayed offset value should be checked against limits on the vehicle test card. If the
displayed value is outside these limits, either the transducer or the test cable is faulty and must be replaced.
This is another form of self-test. The offset is performed when each transducer is connected. All tests
requiring offset are identified by an asterisk (*) on the flip cards and by OFFSET LIMITS on the vehicle test
cards. The offset test is performed with the test probe cable or transducer connected to the VTM. Care
should be taken to see that no stimulus is applied to the transducer. Test probe cable leads should be
shorted together. To perform an offset test, dial the test number into the TEST SELECT switches. Press and
hold the TEST button until the prompting message CAL appears on the display. A few seconds after release
of the TEST button, a number will appear. This is the measured offset value associated with the test probe
cable or transducer and cable.
d. Control Tests. These tests are used to change (or control) the way a vehicle test is displayed or the
way it is run. There are four control tests:
01 Interleave (displays rpm with next test).
02 Display Minimum Value for next test.
03 Display Maximum Value for next test.
04 Display Peak-to-Peak Value for next test.
Control tests 01, 02, 03, and 04 specify the action to be taken by the next test only.
A subsequent test will reset the control.
1. Interleave (Test 01). This test alternately measures engine speed and a second parameter such as
fuel pressure or alternator voltage. To initiate interleave, dial 01 into the TEST SELECT switches and press
and release the TEST button. The prompting message PASS will signal the technician to dial in the second
test number and again press and release the TEST button.
2. Minimum Value (Test 02). This test displays the minimum value measured during a test. To
initiate a minimum value display, dial 02 into the TEST SELECT switches and press and release the TEST
button. The prompting message PASS will signal the technician to dial in the desired test number and again
press and release the TEST button. The minimum value is displayed and updated whenever a lower
minimum value is measured. Entering 02 and the test number again will reset the process and a new
minimum value will be displayed.
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