Q: is the ecm the problem if battery light is on and the alternator isn't bad

asked by on October 11, 2016

battery light is on and the charging system doesn't keep battery charged, alternator replaced as well as battery and no change to problem, the wire from alternator to battery block in engine compartment burns out and any direct wire made from alternator to battery block burns up - do not know if wire was damaged before old alternator was replaced, the actual battery is in wheel well, being told the ecm is culprit, the engine light is not on only the battery light, was told the voltage regulation of system is in the ecm for this year of car

My car has 87000 miles.
My car has an automatic transmission.

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This is likely a sign of a failing voltage regulator. This is a unit that regulates the charging of the battery by the alternator. In your case, it sounds like the voltage output from the alternator may be much too high resulting in overcharging the battery and burning up wires in the process. I would recommend having an expert from YourMechanic come to your location to diagnose and properly test your vehicle’s charging system.

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