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Q: Is my alternator bad or my cables?

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The car will not keep a charge and will not start. I have replaced the battery and the starter. If I connect my battery charger to it, the lights come on , but no start. Once I take the charger off, nothing in the car works, not even the lights.

My car has 19500 miles.
My car has an automatic transmission.

Hello. If the vehicle is only working when the charger is installed then there is high resistance in the vehicles electrical system. Most of the time it is caused by a bad positive battery cable. I usually do a voltage drop test of the positive and negative battery cables to make sure that they are fine. If they are then I test the resistance going to the fuse box as high resistance in that circuit will cause this also. If you are planning on having this no electrical power problem checked, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this.

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