2003 Taurus only starts with boost but alt and bat are good
I can only start my car with a boost. The alt charges the battery with 12.6 volts and the battery has a full charge. When I try to start the car without a boost, the dash lights are weak and there is clicking that comes from the relays next to the battery. Everything will work until I try to engage the starter. That is when the clicking starts and the dashlight go weak. But no action from the starter. When I attach the booster cables, everything works and the car fires up with no issues. I can drive it and as soon as I turn it off, I need a boost to start. Any ideas?
Full charge on a 12 volt battery is actually 12.8. If your alternator is only charging at 12.6 volts it has failed. Charging voltage should be in the neighborhood of 14.5 volts and within a couple tenths of that with the heater fan on full and headlights on. Take your car to your local Advance Auto Parts and they will test the system for free.
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