i am having an issue where my battery is dying after leaving the car for about a week without starting it. i have a brand new redtop optima battery and was having the same issue with the previous battery. im wondering if you guys have ever had this issue and if there are common areas that draw down the battery to look at first before i dig deep into the wiring. any help would be greatly appreciated.
It's usually an add-on, like an aftermarket stereo, alarm, led light setup, etc...
Easy way to find out is to take off the positive terminal from the battery and connect a test light between the battery and the cable end. With all accessories off and the doors closed, the light should be off. If it's on, simply go inside and remove fuses from the panel and reinstall one at a time them until the light goes out (make sure the interior lights are off while you do this, so they don't draw and keep the light lit). Whichever fuse makes the light go out when you pull it contains the shorted circuit.
it's very likely also that it's the alternator field draining, which won't show up in the fusebox test, because it has it's own circuit, so disconnect the ignition harness at the inline fuse and see if the light goes out after the fusebox test.
The clock is constantly running and drawing current from the battery and it will reduce the batteries longevity if this constantly is happening ( constantly drawing down the battery )
It will draw down the battery in a period of time if the car is not used as is often the case with our Cadillacs
You can use a smart type charger to keep the battery topped off —or disconnect the negative terminal of the battery when the car is sitting idle and reconnect it when you use the car
I recommend disconnecting the neg terminal until you find the source of the battery drain to protect the battery from wear and a reduced life span
The above only applies —if you do not have a short in your electrical system then use Mark’s suggestions to track down the short would be the way to go
In addition to the suggestions I would also make sure the battery is good and doesn't have a bad cell etc by disconnecting the battery cable and taking all load off if it. Get voltage measurement after about an hour after engine is shut off then go back in a couple of days, It should be basically the same, with hardly any drop. I have battery I keep in the counter for testing stuff and it stays basically the same months on end with no current draw.
You will also obviously want to check "switched" lights like the trunk light, glove box light, and of course the interior lights to make sure they are off when you think they are off.
Just to add on the fuse box text, you can also just use an ammeter in place of the light if you have one to get an exact amperage draw reading. There is also a chance the short is between the battery and fuse box in which case the pulling. fuse trick will not help, but would still let you know you still have a short with all the "fused" circuits disconnected,
Pull the body feed fuse and use a test light with an additional alligator clip. Clip the test light to the clips on the body feed fuse slot. If the light lights up, the draw is in the body feed section. Push the door jamb switch button in to shut the interior lights off so see if the test light goes out.
If the light stays on, you will need to find what section of the wire harness the draw is in. Disconnect the left section at the left kick panel. If the light stays on, disconnect at the right kick panel. If the light stays on, the draw is in the dash somewhere.
The clock, glove box light, ash tray lights dash lights.
If the body feed fuse is not the culprit, pull each fuse and use the test light to see what fuse lights up.
The ignition wire harness is not protected by fuses, so test that also. It connects to the bottom of the fuse panel.
In my experience, window switches are a possible culprit. Any electrical gizmo potentially is.
My suggestion is to use Diehard Gold batteries, which are still made in the USA. Optimas are not good in my experience.
I always install a good quality in line battery switch, not the cheap brass one for battery terminals which go bad after a while.
Always use a trickle charger when the car is sitting. GENIUS ones are great.