Troubleshooting Troubleshooting Troubleshooting Tool 1. Jumper Wire Electrical Malfunction Troubleshooting 1. Wire Harness Troubleshooting Following 6 steps help to diagnose and troubleshoot wire harnesses. Be sure to check any non-genu- ine components added to the vehicle before performing any diagnosis. If the vehicle is equipped with such components, disconnect them to confirm that the added components are not the cause of fault. To troubleshoot the wire harness, perform the following steps: (1) Confirm problem. (2) Look for any related symptoms (by checking components in same circuit).
(3) Analyze symptoms (use circuit diagram to determine circuit layout, areas most likely to fail, and areas to proceed with diagnosis). (4) Isolate the failure area. (5) Repair the failure area. (6) Check if it is working properly (in this step, check if all items of repairing circuit are working properly). 2. Voltage Check Jumper wires are used to create temporary circuits, and connected between circuit terminals to bypass switches. E010090 Warning (1) Determine conditions in which voltage is present at the check point. Ignition Switch • Do not connect jumper wire from power source end to body ground, otherwise, wire harness or elec- trical components may be damaged. Example: 2.
Voltmeter Voltmeter is used to measure the circuit voltage. Measure- ment range should be higher than 15 V. Voltage is meas- ured by connecting the positive probe (red) of voltmeter to positive lead of part to be tested and the negative probe (black) to the negative lead or body ground. [A] - Ignition switch ON 10A RF02 Power Supply Circuit [B] - Ignition switch and switch ON [A] - + V Voltmeter (2) Using a voltmeter, connect the negative probe (black) to a good ground point or negative battery terminal, and the positive probe (red) to the connector or com- ponent terminal. Relay Black - + V [B] This check can be done with a test light instead of a voltmeter.
Light Switch Ground Red 010 012 3. Ohmmeter Ohmmeter is used to measure the resistance between two points in a circuit, or to check the circuit for open or short. 3. Continuity Check (1) Turn off all electrical appliance and ignition switch, disconnect the negative battery cable. Power Supply Line (2) Disconnect the circuit to be tested. Ohmmeter (3) Connect the two probes of ohmmeter to both ends of tested circuit, and check the circuit continuity (lower resistance indicates better circuit continuity). - + Ground Line - + Ohmmeter Switch 011 If the circuit has diodes, reverse the two probes and check again.
When contacting the negative probe (black) to the di- ode positive side, and the positive probe (red) to the negative side, there should be continuity; When con- tacting the two probes in reverse, there should be no continuity. 013 Warning • When applying voltage to the circuit, do not connect the ohmmeter to circuit, otherwise the measure- ment data may be inaccurate or even cause damage to ohmmeter. - + - + Ohmmeter Diode 014 7