The truck started flashing the battery light and eventually it died on me. I installed a brand new alternator and battery and the next morning the light comes back on and the voltage is very low.
My car has 151000 miles.
My car has an automatic transmission.
Hi, thanks for writing in. The charging system is not very complicated. If the alternator and the battery are absolutely 100% good, no doubts about it, then the issue is likely a bad ground. Both the battery and the alternator are grounded to the vehicle. Without a proper ground connection, the circuit is incomplete. To locate the battery ground, find the negative terminal and trace the grounding strap to the body of the vehicle. Make sure this connection is clean, dry, tight, and protected against the weather. Secondly, check the alternator and its ground. Some alternators ground to its case, while some run a ground strap to a part of the body, frame, or a bolt. You will want to trace the negative terminal on the alternator. This too need to be clean, dry, tight, and protected against the elements. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect your electrical system for you, and make or suggest any repairs as needed.
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