一辆南京雨花工程车,在发动机转速稳定时,水温表指示正常;当转速改变时,水温表随之摆动。此水温表是电磁式仪表。检查蓄电池,无亏电现象。笔者首先怀疑水温表电源线是否接触不良,但发现燃油表与水温表的电源线是同一路的,而燃油表工作正常。取一导线从蓄电池直接与水温表连接,故障依旧;再用一导线将水温表与感应塞直接连接,情况也无好转;检查车体与发动机间的搭铁 A Nanjing Yuhua engineering vehicle, the engine speed is stable, the water temperature gauge indicates normal; when the speed changes, the water temperature gauge along with it. This water temperature meter is a magnetic meter. Check the battery, no loss of electricity phenomenon. I first suspect the water temperature meter power cord is bad, but found that the fuel gauge and water temperature gauge power line is the same way, and the fuel gauge is working properly. Take a wire from the battery directly connected with the water temperature gauge, the fault still; then a wire to the water temperature meter and inductive plug directly connected, the situation did not improve; check the body and the engine between the ground