I bought a car with no key. I took out the ignition, but now the battery is toast. The engine looks like it's in good condition, but the car might need electrical work.
A good battery will be the first step in diagnosing the issue. Then a parasitic draw test needs to be completed to see if there is an issue with a draw that may be draining the battery. If a draw is present, then fuses can be removed one at a time until the draw disappears. This will point to the circuit that is suspect. You may want to enlist the help of a mechanic, such as one from YourMechanic, who will have access to the wiring diagram and have the tools/expertise to assist in the diagnosis and repair of the vehicle electrical system.
Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing