Battery constantly Dying

[Kremer210]

I have a 99 Tahoe 100,000 miles, 5.7. Every morning the damn thing is dead. I replaced battery and alternator. No lights are staying on. This morning my wife went to charge it and when she opened the door she noticed a buzzing sound and all interior lights were blinking in sync with the buzzing. Any ideas?
I thought the door switch but havent gotten home yet to look at it. Is there a way to test this? Any help would be GREATLY appreciated.

[Kremer210]

UPDATE: I charged battery all night and it is holding a charge, so I connected all wires and started it. I put my voltmeter on the wire coming from the back of the alternator and it reads 13.6 volts. So I then dissconected negative terminal and used a voltmeter between the termial and wire and it read 3.5 volts. I began pulling fuse by fuse (inside and under hood including relays) and found no drop from the 3.5 volts. I am now lost except for this one thing. My keyless entry remote doesnt work anymore. It has a new battery, but does nothing when any button is pushed. Could this be a sign of something? Or do I just need to take this to shop and pay a fortune.

Thanks

[muff34]

13.6 with everything on ,lights ,heater fan on high etc. I`d go autozone or another one those places that will check your alternator for free. maybe alt/regulator is prob and is drawing the power out of battery. might not hurt to disconnect remote start also ,however if you have pulled the fuse on that circuit its not likely the problem

[DarrenTX]

You may want to double, triple, quadruple check the battery post connection. I had the same thing happen and all it turned out to be was the post connector coming loose and a bit corroded.

I have seen others have the same problem and only finding out after replacing all kinds of parts.

Also, the keyfob won't work if the battery isn't connected or loose as explained above. If you start it and see the voltage less than 13.5 on the dash, it's a good sign there's a bad connection.

[Kremer210]

Okay I have cleaned the terminals (multiple times) and even tried it on the top posts ( my battery has both sets of posts) and had alternator checked by 2 different places, still no answer. My question now is, is how much should be coming out of the battery when its not running? Is the 3.5 volts too much or is that normal? I might resort to pulling out light bulbs in glovebox and under hood. Any other ideas?

[cdc692003]

find your local high school and go to there automotive dept...tell them youhave a test for them and get it fixed for free....

[Kremer210]

I like that idea but most of these kids I see in their autoshop (my cousin is in the highschool autoshop) I wouldnt let work on my 10 speed! Maybe I could look a little farther down the road though.

[Shoerfast]

Going with Muff34 on this one, a breakdown diode in the alternator (even some rebuilds are just checked for charge rate, not a reverse flow)

Just a .10 cent trick is to scratch the negative batt. cable across the neg. post, the darker the better and note the intensity of the spark.

Lots of accessories will make a slight spark, your looking for one that you can almost hear as you spark it. Spark it, disconnect stuff, spark it again, repeat. You may get lucky and find it?

Just a .10 cent check, if you dont like it I will give your dime back!