Bad battery or a parasitic drain
Yes. More so if it is connected. Most vehicles today put a parasitic draw on the battery that will drain it down over time. Parasitic draw should be under .050 mA.
If the defect is causing a parasitic drain, yes.
Bad battery, Parasitic drain.
There's a parasitic drain somewhere.
Parasitic voltage drain is typically power that is being drawn from a power source when an item should be "off". For example; when a car is turned off typically it is still drawing small amounts of power to run a clock or keep an alarm funtioning. This could be considered a parasitic voltage drain. Sometimes in household systems it is also referred to as phantom power. Some companies like Roemtech (which manufactures classroom audio systems) spends a lot of time and money trying to reduce parasitic or phantom voltage drain. This can amount to a lot of power savings over the span of a year.
Parasitic capacitances form across every depletion region there's also a capacitance between the conductive leads to the terminals. For simplicity they are usually just lumped to each of the terminals of the transistor. Gate, Drain, Source and Substrate. If substrate is shorted to source creating typical 3 terminal representation then that half of those parasitic capacitances combine and Css (source-substrate) = 0. Cgd Cgs Cds (primarily from drain to substrate, not drain to source)
Dead cell in the battery, or parasitic drain from a light that is on or a relay that is stuck.
The battery can be brought to many shops for a free test. Otherwise, you can test the voltage and parasitic drain amperage with proper usage of a multimeter, available at most hardware and electronics stores. To test the battery beyond voltage and parasitic drain, a very expensive piece of machinery is required to test it further. Most shops have such equipment.
They wear out over time, there could be a parasitic drain on the electrical system, something might have been left on.
This is caused by one of two reasons. Either the battery has a dead cell and needs replacing or there is a parasitic drain on the battery. The drain can be any light that is constantly on or a relay that is stuck.
The correct spelling is "parasitic."