My 1991 Cadilac Seville has only 24,000 miles on it but the battery keeps going dead like it's being drained, and the radio and antenna are'nt getting any power, is it an ignition problem?

Jeremiah Meyer

• 204 Answers
• Posted on Jan 15, 2009

SOURCE: Battery drain from power door locks on 96 Grand Cherokee

The Module in the Drivers Door is notorius for this problem. I would start by changing that first. Good luck to you. Thanks for using fixya!

-JC

SOURCE: 95 concours battery keeps draining out

CHECK THE FUSE OF THE ALTERNATOR OR CHECK IF THE ALTERNATOR IS CHARGING

SOURCE: battery keeps going dead

I have a 2008 Jeep Grand Cherokee. The battery and alternator have recently been replaced, but sometimes my car still won't start. I'll put the battery pack and it and charge it and off it goes with no problem, then a few days later the same problem occurs. The cables have been cleaned. Any thoughts? Thanks

SOURCE: Cars battery drains every night. local car repair

One by one, disconnect the fuses until you see no change on a volt/ohm meter connected to the battery with the engine not running.

SOURCE: 05 jetta gls- battery keeps going dead- had

I think you answered your own question; I highly suspect the amp.

I am an experienced audio repair tech. Your description infers you have a separate amp; it should have a heavy power, a heavy ground, and a light remote (to the amp on and off). If the power and remote are tied to battery+, then the amp will run all the time. The proper way to install and amp is with the wire to a switched source; key ignition run or assy position; or to the power antenna wire (usually blue, maybe orange or yellow?*) of the radio (best solution, runs only when the radio runs).

*I did repairs, not installs, and did not pay much attention to wire colors.

Usually red, black and yellow are power and memory power into the radio. the other color (blue?) is probably the power antenna (or 'antenna relay' lead) lead that raises a power antenna when the radio is running if connected to a motorized antenna. Other wires are in pairs by matching color and color strips schemes are the speaker leads. Often there is a wiring diagram sticker somewhere on the radio chassis. Sometimes they are embossed on the back or top as recessed characters.

I also suspect your amp has a blown channel and is drawing idle current through the speakers (bad for speakers) or the amp chassis. I don't think an amp running would drain a battery unless left sitting without driving for several days. On the other hand, a damaged amp could draw excessive current though the damaged channel(s) and drawn down the battery in short order (and possibly be cooking your speaker coil wires).

IIR amps draw about 1/2 amp or less at idle (unless VERY big) and say a battery is 66AH. A half amp would take 122hrs (more than 4 days) to fully drain the battery. I think batteries are typically ~60-100 AmpHour capacity.

I can't comment on the car alarm, don't know what their power consumption conditions are.
Start with the amp, disconnect it's power and remote wire and see if your drain problem goes away.
The 'thump' is suspicious (is it equal?, or just in certain channels [speakers])?. If it's just thumping in one channel or side, and not present approximately the same in all channels; that channel is probably bad.
You can post back for voltage test procedure to check amp if you need it.

I think you hood switch is not activating when the hood is down, check your hood height adjusters (rubber bumper knobs) on each fender or each side of radiator (ie, is your hood straight?). These screw up and down to adjust hood closure after releasing (turning) the locking springy plate thingy at the bottom, hood alarm switch also likely has a threaded height adjustment, and the hood and switch has to be right, if the switch is not bad internally (or corrode/road salt). If heights are ok, try cleaning the switch with spray switch cleaner (Menards?) (or WD-40 as last resort). If you use WD-40, you must use a spray lube or oil afterward or it will corrode again (I use silicone oil spray for lube). WD-40 is a solvent, NOT a lubricant (google it) and will wash away any oils lubricating and protecting it now.

Post back what you find.