Wiring Harness (Open Circuit) - Test
断路是指使电流不流动的电路故障。 断路通常是由电气导线故障或电气接头连接不良引起的。 电气导线或连接断开时，电路中的电流就会中断流动。 常闭电路的电阻值应小于 5 欧姆。 下述步骤将说明断路测试：
参考有关完整的电气示意图，参考正在维修的机器的电气系统示意图。
测试有无断路。
- 确定可疑电路中的接头和导线编号。 使用机器的电气系统示意图检查电路。
- 将钥匙起动开关和断路开关转到断开位置。
- 从配线线束上断开部件和 ECM。
- 在一个断开的线束连接上，将一根跨接导线连在可疑导线的触点与机架接地之间。
- 在其他机器线束接头上，使用万用表表笔测量可疑导线的触点与机架接地之间的电阻。
预期结果：电阻小于 5 欧姆。
确定 - 电阻小于 5 欧姆。 线束电路正常。
停止。
异常 - 电阻大于 5000 欧姆。 机器线束中存在断路。
修理：修理或更换机器线束。
停止。
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