02 Impala battery drain

I have a 2002 LS model with 81,000 miles. Everything is stock (radio, etc.). I have a parasitic draw on the battery that leaves the battery dead overnight.

I have pulled the negative terminal off the battery and put in an amp meter. After about ten minutes the draw hits a cycle of 1.86 amps for about 20 seconds then down to 0.04 amps for about 6 seconds, back to 1.86 amps, etc.

I notice a clicking sound under the dash and a faint hissing sound on the radio during the cycle. If I pull the CLSTR/BCM fuse there is no draw at all. If I pull only the radio fuse, I get the same cycle, but with 0.48 amps for 20 seconds down to 0.04 for 6 seconds. I have replaced the RAP relay and no change.

If I pull the fuse for the BCM no change. I have read some posts that the BCM can get fried if you jump start the car (which I had to do about 4 months prior to this problem). How do you know if the BCM is bad? Do you guys have any other suggestions? :banghead:

I have a 2002 LS model with 81,000 miles. Everything is stock (radio, etc.). I have a parasitic draw on the battery that leaves the battery dead overnight.

I have pulled the negative terminal off the battery and put in an amp meter. After about ten minutes the draw hits a cycle of 1.86 amps for about 20 seconds then down to 0.04 amps for about 6 seconds, back to 1.86 amps, etc.

I notice a clicking sound under the dash and a faint hissing sound on the radio during the cycle. If I pull the CLSTR/BCM fuse there is no draw at all. If I pull only the radio fuse, I get the same cycle, but with 0.48 amps for 20 seconds down to 0.04 for 6 seconds. I have replaced the RAP relay and no change.

If I pull the fuse for the BCM no change. I have read some posts that the BCM can get fried if you jump start the car (which I had to do about 4 months prior to this problem). How do you know if the BCM is bad? Do you guys have any other suggestions? :banghead:

I have the same problem, with a new battery I can get 2 to 3 days befor the battery is too dead to start my 2001 Impala. I couldn't find a short anywhere so I brought the car into a small shop, (they did $10.00 worth of diagnostics, meaning not much), but found nothing. I am still trying to figure out the culprit.

:disappoin I have the same problem, with a new battery I can get 2 to 3 days befor the battery is too dead to start my 2001 Impala. I couldn't find a short anywhere so I brought the car into a small shop, (they did $10.00 worth of diagnostics, meaning not much), but found nothing. I am still trying to figure out the culprit.

Find out where the clicking is coming from.

Do u have an aftermarket alarm?

cabin cowboy -- well I got it fixed mine turned out to be the BCM. I ordered a replacement BCM from Advanced Auto for $100 and then called around to the dealers until I found one that would only do the reprogramming and they charged me $95. We took it on a 500 mile road trip over the weekend and so far haven't had any problems. The dealers wanted between $500-600 to replace and reprogram the BCM which was a complete rip-off, I was just really persistent on this being a DIY fix for me..........good luck!

The dealers wanted between $500-600 to replace and reprogram the BCM which was a complete rip-off
HaHa You think thats steep? A dealership I spoke to wanted $1100 to do it, and it was the one everyone said was really cheap and realiable for GM service.:lol: Ya, right...

I'm kind of discouraged about just buying one and having it programed because have to find a place that ships to Canada with a decent price, and I'm not that keen on online shopping outside of ebay, I might have to bite the bullet and pay $450 to get it done :frown: But your success gives me some hope!

To everyone that has this issue. It is not the BCM (however the problem is plugged into it) I had the same problem and after tons of diagnosing found the culprit and it a free fix (kinda).

Pop your trunk, and unplug the two electrical connectors from the latching mechanism. The soliniod in the release part gets a short causing a dead battery issue over night. I found my battery was always left with 5 volts.

Havent had a dead battery in 4 months now!!! And I dont mind using my key to open the trunk.

To everyone that has this issue. It is not the BCM (however the problem is plugged into it) I had the same problem and after tons of diagnosing found the culprit and it a free fix (kinda).

Pop your trunk, and unplug the two electrical connectors from the latching mechanism. The soliniod in the release part gets a short causing a dead battery issue over night. I found my battery was always left with 5 volts.

Havent had a dead battery in 4 months now!!! And I dont mind using my key to open the trunk.

Well I know mine is the BCM because I took it to the dealer i bought it from (not a GM Dealer though, but a trusted used car dealership) and they couldn't figure it out. They pulled another Impala off their lot and put it's BCM in and it sat overnight, there was no Paracitic load at all, but there was alot of draw with my bcm in the car.

The 2 common causes I find are the RAP module and the BCM. Of course it can be just about anything electrical on these cars since they are riddled with gremblins!

All, I had a similar problem a while ago. The battery would intermittently drain completely. What my problem was/is, is the ignition switch. I could pull the key out without the switch being completely off. What I noticied was that the odometer reading would stay lit and the fuel pump would stay engaged. So my fix is to make sure the ignition is all the way off and the odometer light is off. I can now take the key out of the ignition while driving with no ill effects. Just a crazy problem. BTW, I have a 2000 Impala, 3400 engine... Good luck..............

Hi, I have been struggling with this issue for a few weeks and finally found the problem. History: the radio has been acting wonky and the radio power / volume button does not control the radio properly i.e. when you push the power button, the radio comes on but attempting to adjust the volume, changes the fade, balance and bass controls and further turning of the volume, shuts the radio off. After a few dead battery mornings and recharges, I noticed that with the charger connected, key off and the radio off, I could hear the unfiltered power sound coming through the speakers. I pulled the radio / amplifier fuse and bingo, no more drain. I am reluctant to get a used radio from the wrecker as I don't know if it was the radio or the amp as the root cause. Hope this helps others. regards, Jim