Q: Car keeps dying while i drive. I have a brand new battery and just replaced the alternator a week ago. Dies when headlights are on

asked by on September 04, 2017

Car keeps dying while I drive. I have a brand new battery and just replaced the alternator a week ago. Battery light stays on like there is an error. Only seems to die when I turn my headlights at night. ABS light will turn on and then all my gauges will stop working and then the car will shut off.
My car has a manual transmission.

Although the alternator is new, and presumably working properly, charging system output should still be measured at the battery terminals. You want to rule out a problem in the charging circuit and/or connections to the battery. If charging system output is normal, the amount of current drawn by major circuits running off the battery should be measured. It is possible there is a high resistance somewhere, a bad ground, or a "phantom" electrical load that is not supposed to be there and that can cause a voltage drop, possibly explaining the issue your car is experiencing. To have all the appropriate diagnostic tests performed, the service to request is an electrical circuit/component diagnostic. If you request that, the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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