slow battery drain , not so slow anymore :-(

my car has always had a slow battery drain. so, I keep it on a battery tender. But, it's gotten worse. If I don't keep it on the tender the battery won't even last a day now. Battery is about a year old. Car is a 97 GTS with 11,100 miles.

I've seen other folks saying they had issues the with the engine management computer. Would you all agree that is the lead suspect? sounds expensive :-(

any other lead suspects? stereo is stock, as is the rest of the car for that matter.

I' mafraid to to even take it on an overnight roadtrip now.

G

Do the LEDs in the door handles go off after about 30 secs (after closing door)/does the alarm work like normal? Even so, since you say it wont even last a day it sounds like you may have a major draw somewhere. Have you tested anything/checked wiring yet or just now starting to seriously look into it?

I have not dug in looking for any high current draws yet. I don't think I have a current clamp right now. wierd thing I noticed, It would not start the other day after a very short time since last driven, so I put it on the 1.5amp trickle charger and it indicated it was charged in about 30 minutes or less. seems odd that it would be so dead not to start, but charge that quickly. nonetheless, it started right up after the indiactor said Green!

i may start plucking fuses on non-critical systems to see if the battery holds charge longer.

Regardless of the age of the battery, I would test the battery first (assuming that you negatively answer DrTaco's question above concerning the door LED's and thus the EEM)...noting that by now, battery could be bad by primary or secondary failure. Batteries can fool you. Next door neighbor came home last week in his Durango....went dead on restart with no lights, no dome light...NOTHING. He REALLY did not want to hear that his 23 month old Mopar battery installed at a Dodge dealer was dead...but when I tested it with a volt meter, it read 3 volts. Batteries can go downhill quickly in this heat wave.

After checking battery (and alternator), and if OK... go to IOD test (ignition off draw test) to rule in or rule out specific circuits that MAY be a source of current...including alarm (EEM), engine controller (especially if you mean an add-on type), etc.

Follow IOD protocol carefully...and leave windows DOWN while pulling the various fuses. Much has been posted on this...and, it is well covered in the Service Manual.

A bad battery is my guess.

Since it has slowly gotten worse for you, I suspect the battery is just done... not holding a charge.

However, if the battery checks out okay, find out how much current is being drawn off the system (measuring milliamps). While the meter is connected, you then can pull fuses to narrow down which system is drawing current. If it's the IOD (Ignition Off Draw) fuse, then a common theme seems to be the keyless entry module staying energized due to either a hood switch or hatch switch giving a false signal that either the hood or hatch is open... the alarm doesn't like that.

Maybe an electrical issue? I dont think LED's draw too much current to drain the battery that quickly.

DrTaco said:

Do the LEDs in the door handles go off after about 30 secs (after closing door)/does the alarm work like normal? Even so, since you say it wont even last a day it sounds like you may have a major draw somewhere. Have you tested anything/checked wiring yet or just now starting to seriously look into it?

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coupe said:

Since it has slowly gotten worse for you, I suspect the battery is just done... not holding a charge.

However, if the battery checks out okay, find out how much current is being drawn off the system (measuring milliamps). While the meter is connected, you then can pull fuses to narrow down which system is drawing current. If it's the IOD (Ignition Off Draw) fuse, then a common theme seems to be the keyless entry module staying energized due to either a hood switch or hatch switch giving a false signal that either the hood or hatch is open... the alarm doesn't like that.

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^ this....and You may eventually need to do a test for " parasitic draw" using a 2 amp or 10 amp meter. Harbor Freight sells a cheap but nice one for $3.95...or free if you look at the ad in the back of car magazines.
Also, most times the draw is caused by a non-factory accessory which was added after production.
Also, a difficult to pinpoint draw can be a shorted diode in the alternator.

FYI most cars allow a draw of 20miliamps to 60 miliamps....over that...and you may have a problem.

( this is after waiting for 4 minutes for the modules to go into sleep mode)

My use of "IOD test" (not fuse) referenced above is well described in the Service Manual...and consists of putting multi-meter (set on amps) between negative battery terminal and the negative battery cable with Ingition Off to measure Draw. If high, start methodically pulling fuses to fund curcuit that is problematic. The Viper should not draw more than 35 milliamps AFTER all circuits have timed out (and capicators have drained)...usually stated as 2 minutes, but I have seen it take 5 minutes, noting that hood, hatch and doors are is closed position when I test...hence recommendation to have windows down.

could this be a catch 22 kind of deal, where I have a steady drain that eventually breaks down the battery if I let it sit long enough? i know teh previous owner also went through batteries and his dealer eventually installe the battery maintainer for him. I assumed his issue was he drove about 550 miles a year for 14 years. I'm more like 3000 miles per year, running it almost every week. I know all my other vehicles will sit for months and start up.

Like Steve said, check the battery first... that's where you start.
Did you happen to notice if your gauge indicated it was charging while driving?

A steady enough current draw could indeed hurt batteries prematurely...and in some cases very quickly.

A "tender" only bandaids the wound, although many will default that answer as your solution.
It's not a complex system, but needs the test conducted as per Steve and myself above.

Right on, coupe !! Many of us have indeed "been had" by our coveted battery tenders !! Although I swear by them, a tender CAN mask an impending failure by allowing a great start-up at home of a silently failing battery, then the dead battery manifests on attempted restart. This has happened to me more than once over the past 16 years of "Vipering". Nonetheless, I DO keep all Vipers on tenders and have gotten to the 8 year point on a couple of batteries. These days, however, I tend to change out the batteries EARLY !!

Rolled the dice, and drove it to work today. Observations:

1. alernator/generator is working. Voltage is a solid 14 on the dash guage when idle is above 500 RPM
2. everytime the battery does die, too weak to start and a I try to start, the engine computer has to relearn how to idle. just takes a little driving. but the first few miles it may die when i come off the throttle out of gear.

So, It's in the parking lot at work, and I put this small solar charger on the dash. It is super low power. I'd be surprised if it even kept up with whatever is draining my battery. So, I also brought a jump back to make sure I can get home. we'll see how this story ends about 7:15pm central time

Sorry to hear about your Viper's electical problem. What brand/type of battery do you have? Also, see if there is a manufacture date (probably month/year) on the battery.

I installed a new Mopar battery last year. I'll have to check the manufacture date.

other observations I forgot to comment on earlier.

1. the alarm appears to working normally
2 the dooe LED lights go off shortly after shutting the door.

gtex said:

Rolled the dice, and drove it to work today. Observations:

1. alernator/generator is working. Voltage is a solid 14 on the dash guage when idle is above 500 RPM
2. everytime the battery does die, too weak to start and a I try to start, the engine computer has to relearn how to idle. just takes a little driving. but the first few miles it may die when i come off the throttle out of gear.

So, It's in the parking lot at work, and I put this small solar charger on the dash. It is super low power. I'd be surprised if it even kept up with whatever is draining my battery. So, I also brought a jump back to make sure I can get home. we'll see how this story ends about 7:15pm central time

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Well I don't think anybody expected a viper owner would be getting his car washed 8-10 times a day... those ignition wires are probably all soft and spongey by now!
http://forums.viperclub.org/threads/654785-Bikini-car-wash?p=3091889#post3091889

gtex said:

they actually asked to wash my car. not bad for a work day lunch.

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VYPR BYT 94 said:

Well I don't think anybody expected a viper owner would be getting his car washed 8-10 times a day... those ignition wires are probably all soft and spongey by now!
http://forums.viperclub.org/threads/654785-Bikini-car-wash?p=3091889#post3091889

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I only let them wash it once. then i needed a cigarette and a nap

A couple of insights:

1. Use a battery tester (discharge) and see what the cranking amps are - this will give you the strength of the battery. A voltage test shows you nothing.

2. Cars are all different, but, your at-rest battery discharge should be substancially under 100 mA. The more you are below that number the better. Let the car sit for about an hour before you test it. In other words, open the hood wait about an hour and then look for the current draw. The problem you will have is that you have to get to the battery. Also keep in mind you have more than one battery circuit leaving the trunk area. The best position for a clamp-on ammeter would be the ground conductor at the battery. This would give you total discharge current.The ammeter also has to be a Hall Effect style to work on DC if it is the jaw type.

3. Also keep in mind when you think of a dead battery, that is a battery that is approx 85% -88% of charge. This may not be precise, but, we are in the ball park, a look at a new battery and its amp-hr rating, take 15% of that number and divide the current draw into that number for a dead battery time in hours. As an example a red top is 50 amp-hrs, 15% is 7.5 amp hours, therefore, a 100 mA (arbitrary battery leakage) discharge is 2.4 amp-hrs per day,that means you will have a dead battery in approx three days at 100 mA. If the current draw is a little more and a you have a slightly bad battery you will get there much quicker. There is one more issue, if the battery has died several times, your amp-hour rating has been reduced dramatically, at that point battery age is not relevant.

i went ahead and replaced the battery. I noticed on the Mopar battery had a sticker labeled 07/09. I think they sold me an old battery last year :-( I shoudl have gone back and complained, but I'm sure they woudl have pro-rated teh value to almot nothing. anyway, I went with Gold series from Advance Auto parts. I know I probably still have a slow drain that may be substantial, but I got no help from that old battery :-( we'll see how the new battery holds up. I'll still be using the tender since it's not driven that often.