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Battery drain

steelersfan1960

New Member
Joined
Nov 30, 2014
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2
Does anyone have an idea why my 2002 1500 drains the battery if I don't start it ever couple of days?
 
Anything connected to the battery could be drawing too much when engine is off.
 
I bet I'd the light on the dashboard same thing happen to me in me 2005 they come loose and yor battery will drain check you tube how to fix it
 
To diagnose you'd want to perform a parasitic drain test, basically checking every circuit to find the one using the most amps when it shouldn't. Here is one such video on a 2003 chevy, but search youtube for many others.

Having said that, I've read others have similar problems stemming from the instrument cluster, just like Mant 2005 stated.
 
Here's an alternate way to check for parasitic draw on specific circuits. This indicates the current going through a fuse by the voltage drop across it. Advantage is that you don't have to disconnect a fuse to tell which one has the draw (and potentially wake up different modules to draw current). Works very fast and doesn't disturb the vehicle. Doesn't blow the fuse in your meter if you exceed 10 amps.

All modules should be asleep by 30 minutes after ignition off and door close. So roll down the driver's window, pop the hood, and take the cover off the underhood relay center. If you have an underhood light, disconnect it. Wait 30 minutes for everything to fall asleep.

Using a digital volt meter, probe across both sides of each fuse and compare the reading to that specific fuse in the link below. Once you have the circuit identified, you will have to look in the factory wiring charts to see what is on that circuit.

Probably anything less than 100mA draw should be OK on a battery suitable for an Avalanche. Lower is better. Modules can draw as much as a couple of amps at first key off.

https://www.powerprobetek.com/wp-content/uploads/2018/12/fuse-charts.pdf

Here's info on the reserve capacity of batteries and parasitic draws. You don't want to run your car battery down much or it will dramatically shorten it's life. Car batteries are not "Deep Cycle" batteries that can survive repetitive significant discharges between charges. Car batteries are made for brief high current discharges, followed by complete charging. Just don't let you battery keep going below 12.4 volts when resting at 75F. If you drive it enough, then great. If you don't put a battery maintainer on it.

https://www.optimabatteries.com/experience/blog/what-is-normal-for-parasitic-draw
 
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