Dead battery, again ... locating parasitic draw

[HUMTECH]

Try removing the "AMP" fuse in the under hood fuse box and let it sit overnight see if the battery still drains. Have had issues with the staying powered up and killing batteries. If that doesn't work try again removing the "HVAC" fuse have also seen instances of the hvac module staying awake causing a high draw.

[ree]

Well it happened again Saturday was very humid and drizzly. I had the defrost on to reduce fogging. Sunday morning, dead battery. I'm 99.9% confident that it's related to the defrost and humidity now.

It's going to the dealer for other stuff. I guess I'm going to have to give it up for a long time for them to be able to reproduce and diagnose...or maybe I should never turn on the defrost again.

[TXSUT]

Originally Posted by ree

Well it happened again Saturday was very humid and drizzly. I had the defrost on to reduce fogging. Sunday morning, dead battery. I'm 99.9% confident that it's related to the defrost and humidity now.

It's going to the dealer for other stuff. I guess I'm going to have to give it up for a long time for them to be able to reproduce and diagnose...or maybe I should never turn on the defrost again.

Did you ever get this resolved? I had my OEM battery die on Thursday of last week, so I mindlessly replaced it with an Optima. Now, 3 days later, the Optima is dying. Any help would be greatly appreciated.

-Pete

[ree]

Nope. I've had one more mysterious dead battery since May, but that's it. It's so spurious that I've just decided that I'll live with the deep cycle battery + jumper.

If it's happening regularly for you, take it in. If it's no longer under warranty, you're concerned about the cost of diagnosing it, and you have some educated guess about what system might be the culprit, it might be worth investing in an ammeter. Wire it into your + terminal hookups and note the discharge rates at periodic intervals times while the vehicle is off. I'll look in my manuals for in-spec current's to expect (no promises I'll find the numbers). Then if you seem something larger than those, start pulling fuses in the systems you think might be to blame until the current measured by the ammeter drops to expected levels.

[dochummer]

Originally Posted by ree

Nope. I've had one more mysterious dead battery since May, but that's it. It's so spurious that I've just decided that I'll live with the deep cycle battery + jumper.

If it's happening regularly for you, take it in. If it's no longer under warranty, you're concerned about the cost of diagnosing it, and you have some educated guess about what system might be the culprit, it might be worth investing in an ammeter. Wire it into your + terminal hookups and note the discharge rates at periodic intervals times while the vehicle is off. I'll look in my manuals for in-spec current's to expect (no promises I'll find the numbers). Then if you seem something larger than those, start pulling fuses in the systems you think might be to blame until the current measured by the ammeter drops to expected levels.

Don't know if this helps, but the last time my battery died completely, I had noticed some of the instrument lights were on - The odometer reading, and a couple of panel lights to the rear seat heater and radio controls. That was it. We were camping, and had the interior lights set to 'off' with the rear hatch open for quite some time. When I went to close the hatch is when I noticed those lights. I figured they would turn off by themselves...but in the morning, the vehicle was completely dead.

[TXSUT]

Originally Posted by ree

If it's happening regularly for you, take it in.

Yep, took it in this morning. We'll see.

Thanks,

Pete

[HUMMERcustoms.com/TAZ]

Sorry to get in here late. Most likely they will tell You a faulty front passenger seat adjustment switch. I do not understand why there has not been a recall on these. It seems if you have a passenger and they adjust seat the switch will be stuck in a closed position and draw current for 2 or 3 days and if not driven daily battery will be dead. I worked with my dealer on this trying different things to help them have an answer. They suspected it but, i played with it by wiggling the switch after shut down of engine and other things. I finally confirmed that it was seat switch they changed out and never had a problem a gain.

But, I do know others on this forum have found other things that caused problem. My dealer for 2 years now have found this to be the problem most of the time not always.

TAZ

[HUMMERcustoms.com/TAZ]

Sorry to get in here late. Most likely they will tell You a faulty front passenger seat adjustment switch. I do not understand why there has not been a recall on these. It seems if you have a passenger and they adjust seat the switch will be stuck in a closed position and draw current for 2 or 3 days and if not driven daily battery will be dead. I worked with my dealer on this trying different things to help them have an answer. They suspected it but, i played with it by wiggling the switch after shut down of engine and other things. I finally confirmed that it was seat switch they changed out and never had a problem a gain.

But, I do know others on this forum have found other things that caused problem. My dealer for 2 years now have found this to be the problem most of the time not always.

TAZ

[TXSUT]

Thanks Taz, I'll pass that along to them. They've charged the battery and keeping it overnight to see if the problem repeats. I guess they have to rule out a weak off-the-shelf battery first.