QuestionQUESTION: why does my cd player shut off then comes back on when at a high volume when my truck is off but when the truck is on it plays just fine at high volume
ANSWER: When engine is off the battery voltage drops down to a level insufficient to keep the cd player and/or the amplifiers going. This could be, also, because of an old battery that has lots of internal resistance. A new battery may be needed. Or, if the amplifiers are big power it may be they are pulling lots of current that is loading down the battery.
When the engine is running the alternator is keeping the voltage system up.
If you can tell me the car make and model and the cd player, amps and speakers I can give you a more scientific answer, but my comments above may give you sufficient understanding.
Let me know if you want more.
C
PS: High volume settings, especially with lots of low frequency bass, draw very big current from the battery.
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QUESTION: my truck is a 1998 dodge ram 1500 with a Jensen VM9311TS cd/dvd player with a built 17 inch touch screen. it has factory speakers and no amp.
AnswerYes, when the engine is off your system draws enough power to pull the voltage down too far.
When the engine is running the alternator keeps the voltage high enough to keep the amps running.
You may need a new battery or larger gauge wires from the battery to the Jensen unit.
That would by my best diagnosis.
Do you have a vom? If so, put the voltage lead on the 12v line as it enters the Jensen unit and see how low it drops when the volume goes up. Full voltage from the battery is nominally 13.2v. When it loads down it can drop to 10v. Most amplifiers will start dropping out if the voltage drops below 10v.
Hope this helps.
C
