My truck won't start. When I jump it off, it runs fine until I turn it off. Then it is completely dead again, and it doesn't matter how long it runs.
Hi. Generally, a charging system problem will illuminate the battery light in the instrument cluster and the engine will quit as soon as the battery is discharged. With that being said, the problem either lies in the battery itself, or the connection between the battery and the power ground connections. If the battery can be fully charged and passes a load test, then battery cabling needs to be checked for signs of overheating. This can be done by looking for areas on the battery cables that appear melted or have have a white flaky buildup on them. You may want to enlist the help of a mechanic, like one from YourMechanic, who has the equipment to inspect the battery and conduct the necessary voltage drop tests to track down the cause of the discharge scenario.
Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing