2002 GMC Sierra Battery dies often

VETTEDRIVER96

MEMBER
2002 GMC SIERRA
V8
2WD
AUTOMATIC
170,000 MILES

I have a 2002 Sierra truck that seems to have a problem with a constantly dying battery. I have noticed that if the truck sits for more than 3 days, the battery will be dead again. I noticed the other day that when I turn the truck off, after about 5 seconds the fuel gauge will make a click and turn back on. None of the other gauges turn on though. Could this be what is draining the battery so often? Or is this a normal thing for these trucks, none of my other cars do this when they are turned off. Other than that, I can't find anything else that may be draining the battery.

1 Reply

WRENCHTECH

MECHANIC
20,757 POSTS

The first thing you want to do is have the battery itself tested to make sure it's capable of retaining a charge.
Once you confirm that you have a good battery.

There is a procedure for finding a battery draw like that.

You will need a digital ammeter and a jumper wire with clips on the ends to do this.
First rig any door switches so you can have a door open without triggering the interior lights and unplug the hood light. Remove one battery cable and attach the meter in series between the battery cable and battery post. Take the jumper wire and also attach it the same way. Leave the jumper wire on for at least 10 minutes to expire all the automatic timers. Now remove the jumper wire and read the meter. Anything over 50ma is too much draw. The way you locate this is to start removing fuses one at a time until the meter drops to normal level. This will be the circuit with something staying on. Determine what components are part of that circuit and check them individually until the problem is isolated.