Car started when I jump started it, I guess my battery?

VAMSSS

MEMBER
2004 BMW 325
6 CYL
4WD
AUTOMATIC
67,000 MILES

I have seen lot of lights 1) its the CBS I guess the triangle with a circle covered(yellow) 2)ABS(yellow) 3) brake(red) 4) battery (red). And It started when we jump started using the cable connected from another car and it went down in a mile and we have to jump start again, and the engine pick up or performance is not as it before, couple of days before happening this I noticed a weird sound from the engine but the car started when I jump started it, I guess my battery is dead completely and needed to be replaced? Any suggestions what might have happened?

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

It sounds like you might have an issue with the alternator. When the alternator goes bad it is unable to keep the battery charged and it will drain the battery as you drive. This will stall the engine when you come to a stop. Typically you can restart it but it will stall again.

First test the alternator output to the battery. This can tell you if the alternator is bad.
Here is a helpful video:

https://youtu.be/Z-p4dMJUpUw

https://www.2carpros.com/articles/how-to-check-a-car-alternator

I have attached diagrams for your reference.

Please let me know of any questions.
Thank you.

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