INSULATION 5201232 - Caterpillar

Troubleshooting Methods
Many of the connections between the harnesses on the 215 are made with rubber connectors. If these connections are not tight they can be the cause of electrical problems, either permanent or intermittent (come and go). Make sure the connections are tight before other tests are made.The 5P7277 Voltage Tester can be used to check a circuit for voltage. The 8S4627 Circuit Tester can be used to test circuits for continuity (circuits without voltage).
5P7277 VOLTAGE TESTER
6V3030 DIGITAL MULTIMETERThe 6V3030 Multimeter can be used to do the same functions as the 5P7277 and the 8S4627. The multimeter will measure voltage or circuit continuity. For instructions and use of the 6V3030, see Form SEHS7734.Failure of an electrical component can cause or be caused by the failure of one or more components. Always find and correct the cause of the electrical component failure before making a replacement of the component.
8S4627 CIRCUIT TESTERDiodes
Silicon diodes are used in the 215 Excavator electrical system in the 1V9633 Diode Assembly. The purpose of a diode is to permit current to flow in one direction only. Diodes are shown on schematics as: The actual diode can look like this. If the voltage on the anode side of the diode is more positive than the cathode voltage (.9 volts), current will flow through the diode. If the voltage on the anode side of the diode is less positive than the cathode voltage (less than .7 volts), current will not flow through the diode. The shape of the diode symbol is an indication of the direction that current can flow if the voltages are correct at the anode and cathode.When checking diodes with the 6V3030 Multimeter, the following procedure must be used: The special diode test function allows accurate measurements of forward voltage drops across diodes and transistor junctions. A constant current forces 5 ma of current into the semiconductor (diode) junction under test which results in the voltage drop being displayed on the digital display. This function also permits measurement of in-circuit semiconductor junctions with as little as 200 ohms of resistance in parallel with the diode. The limited current produced by the instrument in the Diode Test Function minimizes the possibility of damage to low power semiconductor junctions.1. Connect the red test lead to the V- Input Connector and the black test lead to COM Input Connector.2. Set the Function/Range Switch to the Diode Test position.3. If the semiconductor being measured is connected to a circuit, turn off the power to the circuit being tested.4. Connect the test leads to the device.5. Read the forward voltage drop on the digital display. If the digital display reads OL, reverse the lead connections. The placement of the leads when the forward voltage is displayed (normally 600 to 900 mv) indicates the orientation of the diode. The red lead is then connected to the anode and the black lead is connected to the cathode as shown below. If OL is displayed with both lead connections, the diode is