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Q: lights dim , radio shuts,down all rear lights come on in flashing mode when accelerating.

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Alternator putting out 16.5 volts when accelerated. Is the alternator regulated by: internal alternator regulator, PCM Unit or Body Control Module?

My car has 57000 miles.
My car has an automatic transmission.

Hello, thank you for writing in. On your vehicle, there will be a "voltage regulator" located on the inside of the alternator. It will be controlled by the PCM. When dealing with the charging system it is important to have the battery tested as well. While it can be the cause of many strange electrical symptoms, a failing alternator can also put extra strain on the battery causing premature failure. Both of these can be tested at most automotive parts stores. 16.5 volts when accelerating is extreme, but it may be trying to compensate for a battery issue detected by the PCM. For more diagnostic help, contact our service department to schedule an appointment.

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