Reasons Why Jump-Starting a Car Battery Fails to Start the Engine?
2 Answers
Here is an introduction to issues related to jump-starting a car battery: Possible reasons include severe depletion of the old battery's charge, jumper cables being too thin (resulting in insufficient current to start the engine), or improperly clamped jumper cable clips. Below are some methods to address a dead battery preventing engine start: 1. Push-Start Method (for manual transmission vehicles only): Push the car to reach a certain speed, then engage the gear and quickly release the clutch pedal while pressing the accelerator. Once the engine starts, immediately depress the clutch pedal and control the throttle to prevent stalling, then slowly pull over to park. 2. Jumper Cable Method: First, locate another vehicle with a functional battery and a set of jumper cables. Position the two vehicles close together, open the hoods to locate the batteries, then connect the jumper cables—positive to positive and negative to negative.
I've also experienced the frustration of a car battery jump-start that didn't work. A friend once tried to jump-start my car with his vehicle, but after much effort, it still wouldn't start. There are actually several possible reasons: first, operational errors, such as incorrect cable connection sequence or loose clamps preventing current flow; second, my battery might have been completely dead with internal short circuits, making jump-starting ineffective; third, the vehicle itself could have issues, like a faulty ignition coil or locked ECU system; another possibility is that the donor car's battery didn't have enough power, with voltage too low to crank the starter motor. In the end, I called a mechanic who diagnosed the problem as a faulty starter relay. Replacing the component solved the issue. So, when facing such situations, don't stubbornly persist—get a proper diagnosis before seeking professional help.
