TM 9-2320-361-20 2-20. STE/lCE DESCRIPTION AND OPERATION (Contd) (2) Pressure Transducers. The pressure transducers have a small breather hole on the side of the housing which should be kept unplugged. Do not use high pressure shop air to clean transducers. (3) Pulse Tachometer. Ensure that slotted hole in engine tachometer drive shaft is clear and not hard packed with lubricant before installing pulse tachometer. (4) Threaded Adapters. Observe threaded fittings carefully to avoid engaging straight threads with pipe threads. Each measuring device (transducer) in transducer kit has its own identification resistor. The VTM uses this identification resistor to check that correct transducer is connected for measurement being made. If the correct transducer is not connected, error code E002 will be displayed. 2-21. VEHICLE TESTING a. General. To troubleshoot a vehicle problem, the technician can use STE/ICE (vehicle test meter and transducers) and vehicle test card. b. Offset Tests. STE/ICE VTM performs a test by setting TEST SELECT switches to test number and pressing TEST button. For some tests, an offset test is required before test itself can be performed. This is done by selecting number of desired test and holding TEST button down for several seconds. The offset test voids characteristic differences in VTM, test leads, and transducers. It “zeros” meter. Once offset is performed, VTM automatically corrects for offset before displaying measured values. Displayed offset value should be checked against limits on vehicle test card. If displayed value is outside these limits, either transducer or 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 flip cards and by OFFSET LIMITS on vehicle test cards. The offset test is performed with test probe cable or transducer connected to VTM. Care should be taken to see that no stimulus is applied to transducer. Test probe cable leads should be shorted together. To perform an offset test, dial test number into TEST SELECT switches. Press and hold TEST button until prompting message CAL appears on display. In a few seconds after release of TEST button, a number will appear. This is a measured offset value associated with test probe cable or transducer and cable. CONNECTOR KEY LOCATION 2-156