Q: Battery over charging new alternator new voltage regulator and new battery

asked by on January 02, 2018

Alternator over charging battery reads 17v. New battery, alternator and external voltage regulator.

My car has 157000 miles.
My car has an automatic transmission.

Battery will not hold a charge Inspection $79.99 - $99.99 Get a Quote

Hey Joe. Thanks for sending the question today. When an alternator is reading higher than it should, there are three possible sources. Either the ECU which controls the production of the alternator is damaged, the alternator itself has an inner short or is incorrectly installed, or one of the wires that comprise the charging system is damaged. Locating the root source often requires an on-site inspection from a professional mechanic.

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