Battery Discharge Problem

OK, so I have a 2006 Lincoln LS with 10K miles. Only weekend driving and never any problem with the car since the day I bought it. However I did a sound upgrade that included 2 amps (Alpine MRP-F450 and MRP-M450) with a capacitor (2.0 Farad). Being in NYC I also decided it was important to add an alarm system (Prestige APS887A). The sound was installed first and 2 weeks later the alarm was put in. No problems. After letting the car sit for 4 days of inactivity, the battery would completely discharge. After going back to the installer, they checked all connections and determined that there was no extra drain on the battery just normal use. I still had this problem. I then put in a Optima Yellow Top battery and seemed fine after a couple of months. When winter came around and it started to get cold outside after 4 days of the car sitting with no use, the battery would completely discharge again. I thought that installing this particular of battery would have fixed it. After repeated visits to my installer and dealer, they claimed that there is normal use on the battery with no extra drain. I am confused thus far and hoping for any other suggestions.

Could it be I am having bad luck with buying new batteries?

Thanks
Rks319

Maybe they mean normal drain for a car with a leaky 2.0 F cap. If they are the ones that installed the system and they are the ones that will have to figure out what's happening if they admit there is a large drain, they will not be inclined to "find" a significant drain, potentially.

I'd suggest you find someone with a DC current meter capable of at least 10 amps and check for drain yourself, or try another shop.

If you opt to check for yourself, have a test light or similar handy to charge up the cap prior to connecting the current meter in series. If the capacitor discharges quickly after the battery is disconnected, then it will appear as a momentary dead short when the meter is installed and blow the fuse in the meter. Insert the test light in series with the battery cable to charge up the cap. As the bulb dims, the cap is getting charged up and you can quickly install the meter. Or, you can just leave the test light installed with the meter also connected.

Does your 2.0 F cap have a voltage display on it that stays on all the time, or do you have a distribution/fuse block with voltage readout that's always on? If so, that could be your drain.

You could also pull the fuses for the amps and deck to see if the drain goes away with them disconnected. If so, the install is the issue. I won't say it's a problem, they will all draw some amount of standby current. Maybe you need to get in the habit of pulling the fuses for them, or put them on a high current switch that you can flip when you are going to be away from the car for more than a day or two. If the drain is just due to the amps or the cap, you could pull the fuses for them without resetting the clock and settings on your deck.

-Rod

There is such a big demand for juice these days !:evillol:

The electronic Ign,fuel pump,computers,Ipods,GPS,sound system,Air cond,
and digital dash.:iceslolan

TURNING ENGINE OFF::naughty:

1) Always turn everything OFF.
2) LET her run for alittle while to charge + cool-off.
3) Than turn her off.

START-UP ENGINE:
1) Every thing should still be off.
2) Start Engine.
3) Let eng warm up befor you turn everthing on!


MCGIVER

Thank you very much. Will try these suggestions and see if i can finally get this issue resolved.

If you haven't found a solution to your problem yet, I'll share a strange experience with you.

I bought a 2000 LS V6 from a friend of mine last year. He had replaced the battery three times because it kept draining after sitting for a few days. Dealership was more than happy to sell him new batteries and told him they weren't sure what was going on.

Turns out the spring-loaded light switch in the trunk was broken. When you would close the trunk the light would stay on. About a 2 minute simple/cheap fix that eluded techs for months.

May not be the problem you're dealing with, but it's worth looking at.

Harold

Other common hidden drains are the glovebox light and the hood light. The trunk is easy to troubleshoot, fold one of the rear seat backs down, close the trunk lid and look into the closed trunk from the backseat.

The glove box light and hood light are a bit trickier.

-Rod