GUAGE ASSEM. 3V3964 - Caterpillar

Introduction
The 189-1720 Analog Gauge Tester Group allows the user to test an entire analog gauge system and quickly determine the root cause of a failure on Caterpillar machines. The different analog gauges that can be tested are temperature, fuel, pressure, and articulation. The 189-1720 Analog Gauge Tester is NOT for use with the Caterpillar Quad Gauge.
Illustration 1. 189-1720 Gauge Analog Tester Group.(1) Analog Gauge Tester.(2) 6V-4094 Foam Liner (installed inside of 6V-3073 Case).(3) NEEG2990 Decal (applied to 6V-3073 Case).(4) 6V-3073 Case.Not Shown: NEHS0786 Tool Operating Manual.
Illustration 2. The 189-1720 Analog Gauge Tester.(1) Dial 1 is a 0 to 50 Ohm Resistance Range.(2) Dial 2 is a 0 to 500 Ohm Resistance Range.(3) Dial 3 is a 0 to 1500 Ohm Resistance Range.(4) Dial 4 is a 0 to 34,000 Ohm Resistance Range.(5) Fuse Cap.Benefits of Using the Analog Gauge Tester
* Decreases troubleshooting time.* Reduces replacing good components.* Diagnose gauge system problems to determine if sensor, wiring, or gauge is faulty.* Use with analog temperature, fuel, pressure, or articulation gauges.* Easy to use, hand-held diagnostic tool.Principle of Operation
The 189-1720 Analog Gauge Tester consists of four variable resistors, connected in series, and each variable resistor provides a different resistance range.
Illustration 3. Operational Schematic Of Analog Gauge Tester.The output of the 189-1720 Analog Gauge Tester will be the combination of all four dials. Turning all dials counterclockwise to the "0" setting will make the resistance very low (<2 ohms). Turning a dial clockwise increases the resistance across the two clips of the Analog Gauge Tester to the value indicated by the pointer (white dot) on the dial.The 189-1720 Analog Gauge Tester outputs a resistance, which can be used to simulate a sender's output. By connecting the Analog Gauge Tester in place of the sender in the "sender/gauge" electrical circuit, a good sender can be simulated, which allows the rest of the system to be checked. If the instrument panel's gauge does not properly respond when the Analog Gauge Tester is connected in place of the sender, move up the circuit towards the instrument panel's gauge to find the fault. The Analog Gauge Tester can also be connected at the instrument panel's gauge to test only the gauge's function.Specifications
Using the 189-1720 Analog Gauge Tester
The 189-1720 Analog Gauge Tester is NOT for use with the Caterpillar Quad Gauge.1. Use the appropriate service information (schematic, wiring diagrams, etc.) to locate the sender, wiring, and instrument gauge.2. Identify the gauge type (temperature, pressure, fuel, or articulation) and the Caterpillar part number. The gauge is located in the instrument panel and the part number is usually located on the gauge face.3. Find the part number of the gauge in the specific look-up table (temperature, for example) in the "Gauge Look-Up Tables" section of this manual.4. Find the gauge chart number next to the part number and refer to this chart in the "Gauge Charts" section of the manual. Each gauge type has a separate set of charts. All temperature charts are together, followed by pressure charts,