TM-9-2320-280-20 HMMWV Technical Manual Unit Maintenance Volume 1 Download
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TM 9-2320-280-20-1 2-15. GLOSSARY OF ABBREVIATIONS AND COMMONLY USED TERMS PCB - Protective Control Box, located on the firewall above the brake pedal. STE/ICE-R - Simplified Test Equipment for Internal Combustion Engines - Reprogrammable, a testing system used for performing tests and measurements on the vehicle. In addition to acting as a conventional digital multimeter to measure voltage, current and resistance, it is also capable of measuring pressure, speed, compression unbalance, engine power, and some specialized battery and starter evaluations. It is powered from the vehicle batteries. The complete system includes a vehicle test meter (VTM), a transducer kit (TK), cables, transit case and technical publications. DCA - Diagnostic Connector Assembly, an electrical harness on the vehicle which allows the STE/ICE-R to be powered and to make measurements of key vehicle signals from a single connection. In addition to many basic electrical signals such as starter voltage and current, it includes engine speed and fuel supply pressure. The STE/ICE-R can make TK measurements at the same time that it is connected to the DCA. VTM - Vehicle Test Meter, a box which performs the measurement and analysis functions of the STE/ICE-R systems. TK (and TK mode) - Transducer Kit, a collection of transducers, adapters and fittings which permit the STE/ICE-R to be used as a general purpose measurement system for any application. This allows the STE/lCE-R to be used anywhere that you want to measure voltage, current, resistance, pressure, or speed. TK mode of operation is what you are doing when you use this kit (as opposed to DCA mode where you are using the vehicle’s built-in sensors to make measurements). Compression unbalance - A STE/ICE-R test that gives an indication of any engine cylinders that have lower compression then the average. It does this by monitoring the battery voltage during cranking. As each cylinder goes into compression, the extra load on the starter shows up as a drop in voltage. This works well for finding one or more cylinders that have a compression problem, but don’t forget that it doesn’t give the average compression. If all cylinders are low by the same amount, this test doesn’t find it. Troubleshooting - the process of making measurements and observing the operation of the vehicle to find out if anything is wrong with it and then to locate any problem that exists. Diagnostics - Troubleshooting by following an exact procedure. Test Chain - a series of tests to be followed in a particular order or sequence. It is referred to as a "chain" of tests because they are all connected one after another like the links of a chain. System - a collection of devices which are all related to each other because they depend on each other to do some function or job. For instance, the function of the fuel system is to inject fuel into the cylinders at the correct time in the correct amount and with the correct quality. The collection of devices that are required to do this include the fuel pump, fuel lines, lift pump, fuel filter, injection pump, and injectors. 2-38