How to Detect a Short Circuit in a Car's Electrical System?
2 Answers
Use a wire to short-circuit the suspected faulty circuit and observe changes in the instrument panel's pointer or the working condition of electrical equipment to determine if there is a fault. After disconnecting the suspected grounded circuit section, observe whether the grounding fault in the electrical equipment persists to determine the location and cause of the circuit grounding. Observe the readings of the ammeter, water temperature gauge, fuel gauge, and oil pressure gauge on the car's dashboard to determine if there is a fault in the circuit.
I don't think detecting short circuits in car wiring is particularly difficult, but it does require patience and method. I enjoy DIY car repairs and usually start with the simpler steps, like checking the fuse box to see if any fuses are blown; if so, replace them with new ones and test. If the issue persists, I use a multimeter to measure voltage and resistance. Disconnecting the negative battery terminal is safer, then I inspect the wiring section by section—the point where resistance approaches zero is the short circuit location. I also sniff for any burnt smells in the car or check for damaged, overheated wiring harnesses. Short circuits often occur due to loose connections, water damage, or rodent-chewed wires—I once encountered a fault caused by aged wiring after rain. When repairing, properly insulate the damaged wires or replace them if necessary. After the overall inspection, test whether the functionality is restored. For complex issues, I still recommend seeking professional repair to avoid fire risks.
