I park the car in the garage and about 5-6 days later the battery is dying or completely dead! The car is equipped with an aftermarket alarm that I'm getting ready to pull out completely and I noticed that several power accessories are not functioning such as, power door locks, rear hatch switch, kick panel lighting, under hood service light. I just cleaned up battery terminals and replaced ground wire with a new ground strap while replacing the connectors with gold plated pieces.

Does this mean there is a short somewhere, and how do I find it?

Any ideas or help is appreciated.

 

Not necessarily. Shorts are usually obvious and will normally kill a battery quicker than 5 or 6 days. It's likely the battery has been damaged buy draining it.

Pull the battery and fully charge it up. Let it sit for 24 hours then measure the voltage again. The following chart will show you the current state of health of your battery.

Battery State chart:
Voltage---state of charge--specific gravity
12.75 -----100% -------------1.265
12.70 -------95% -------------1.257
12.65 -------90%--------------1.249
12.60 -------85%--------------1.241
12.55 -------80%--------------1.233
12.50 -------75%--------------1.225
12.45 ------ 70%--------------1.218
12.40 -------65%--------------1.211
12.35 -------60%--------------1.204
12.30 -------55%--------------1.197
12.25 -------50%--------------1.190
12.20 -------45%--------------1.184
12.00 -------25%--------------1.155
11.75 -------00%--------------1.120

In some cases, such as sealed or AGM batteries you won't be able to check specific gravity. Remember that car starting batteries use more and thinner lead plates are are easily damaged if left in an under charged or totally discharged state.

Here's a good tutorial from Fluke on diagnosing voltage drops in car electrical systems.

http://support.fluke.com/find-sales/...418158_a_w.pdf

In some cases the use of a "Smart Charger" will help restore some capacity to your damaged battery. There are other devices you'll see advertised such as "Battery Desulfinators" that claim they can restore the capacity of a dead battery but personally I think it's snake oil.

 

Thanks for the info, I appreciate any and all help... That being said I have a new question.

So the car is equipped with an aftermarket alarm system that was probably sliced and diced to get into the wiring harness and today I went and bought an automatic battery tender which I had set to provide 2 amps and thought that it would re-charge the battery nice and slow. When I hooked it up to the battery the gauge on the charger showed a full charge of the battery and the alarm started going off. The charger then tripped the circuit and shut off. I am thinking that the alarm system needs to be taken out as it is causing havoc with the vats system.

Please... if you have any more ideas or possible solutions post them, I need all the help I can get here.

Thanks

 

I had this happen to my '83 about a year after I got it. My brother is a mechanic, so he checked it out for me. It took him about 4 days to track down the problem. There is a small storage area in the hatch, has a lid. There is a light in there that the switch was messed up. The light was on all the time even if the switch was in the off position. Your problem probably is not the exact same thing, but it could be something like that.

 

I can relate to "slicing and dicing" in wiring systems. It took me 4 yrs to totally rewire our boat. The underside of the dash looked like a birds nest of wiring. It's a miracle the boat didn't burn to the waterline.

Anyhow, diagnosing and locating the source of the parasitic drain is not going to be easy and can take a long time but patience should prevail. The only way is to go through a process of elimination. Start by disconnecting the power source to the alarm system, which as you said, is the most likely culprit. You'll have to do this for each system that's been installed post OEM until you locate the one that's causing the drain. Candidates will be non OEM stereos, fog lights, alarms etc. It'll take time unless you have a specialized Voltmeter like a Fluke that can measure current flow in milliamps & amps. Otherwise you'll have to let it sit to see if the battery goes down.

I have seen batteries that have been damaged due to deep discharge that can actually hold their voltage but have no or near zero capacity. Can you swap out your battery for one that you know is good?

 

There is a potential culprit that not many know about - the fuel pump. In the garage, in the middle of the night, when everything is deathly quiet - open the hatch, place your ear on the hump in the back, and see if you can hear the fuel pump running. A fuel pump constantly running will discharge the battery in about 3-4 days. If it's running with your key in your pocket, then you need a new Oil Pressure Sending Unit (OPSU)

Explaination:

The fuel pump gets juiced from two seperate sources - the OPSU and the ECM via the fuel pump relay.

The ECM - ECM sends signal through the relay to run the pump for a couple seconds to 'prime' the fuel system when the key is turned to "on".

The OPSU - after the 'prime', the pump won't run until the car is started - when this occurs the fuel pump gets direct voltage via the OPSU, and runs constantly until the key is turned off. BUT - there is no fuse, relay, or anything else in the system to keep the pump from running constantly if the OPSU goes bad - the connection is direct from the battery to the OPSU to the fuel pump, ragardless of the key position or any key at all.

This happened in my 1992 RS, and drove me nuts for 2 weeks until late one night it happened to be quiet enough that I could hear the fuel pump running, and the key was in the house!

Check into this before you go tearing out wires - you may save some troubleshooting!