What causes a battery drain in a 2002 Tahoe? Probably coming from the body module or the key.

bnation

What causes a battery drain in a 2002 Tahoe? Probably coming from the body module or the keyless entry.

thecardoc3

There isn't a single cause for a battery drain on any vehicle. There are things that happen to a lot of cars that can be similar but you don't want to start with a guess. Testing is the best way to go and we use a low amps probe and a digital oscilloscope to directly measure the power being drawn from the battery. Sometimes we see a steady load and there are occasions that we see the load pulsing on/off. With the load that turns on/off you might be able to hear something turning on/off like the rear wiper motor on your tailgate. (common failure) With a steady load, you need a very accurate voltmeter (that can measure down to the microvolt range (.00XXX) and we measure the voltage drop across the fuses to find the circuit which is putting the load on the battery. Then we either move the current probe or if available use a second, or third one to isolate the circuit with the failure.

ray80

bnation said:

What causes a battery drain in a 2002 Tahoe? Probably coming from the body module or the keyless entry.

How long before before it drains,overnight, two weeks ?

bnation

2 days

thecardoc3

How much is the battery charged after each time the car won't start?

ray80

How old is the battery, was it a good replacement, how far does it get driven every day and how cold is it lately where you are?