Well I finally went out today to try and find the cause. I disconnected the pos battery terminal and then put a power tester light onto the disconnected pos terminal and the other end to the pos on the battery - sure enough there was enough draw that the power tester light was on (and quite bright too).
I then pulled every fuse from the engine fuse box, one at a time, to find the cause - none made any different. I then did the same exercise with the fuses on the driver side dash area, and again none made any difference???
So now I am confused. Are there are other fuse boxes in the truck?? If not, I guess my issue is with something not first running through the fuse boxes. Being that my truck is stock (no after market stuff) does this make sense. I thought all factory electronics went through fuse boxes??
I've read that the ignition switch can ground itself to the steering column and cause a drain - would this not go through one of the fuses too? If it does not I guess this may be a good place to start - how do I test my ignition switch if it is grounding???
Thanks
Funny part was they called me the next day, said it was fine and to come pick it up. When I got there they explained they could not find a draw and that there was nothing wrong. They tested the battery and load tested it and all checked out. The service manager runs off to get it and... dead battery
They replaced the battery and I haven't had a problem since.
If you can... try a new battery.
Hope that helps.
07 H2 SUT Glacier Blue - Limited Edition
08 H3 ALPHA Carbon Black
Dear GM: PLEASE SELL ME AN HX
Battery in my 03 has been replaced once so far in the 86,000 miles.
Ed
1987 Jeep YJ 403hp sbc 653hp on NOS
1998 Chev Z71
2007 Chev Trailblazer SS
TAIL RATED!
We used to do it that way 40 years ago but used a simple test light. The old ways still work!
2009 H2 Hummer It's here!!
2006 H2 Hummer Gone and missed
1998 993 Porsche Twin Turbo (Last one made)
2006 Baja Performance 88 MPH
2008 GT2 Porsche
2009 DBS
"I object and take exception to everyone saying Obama and Congress are spending money like a drunken sailor. As a former drunken sailor, I quit when I ran out of money"
I did some more reading, and then some more testing. Found tyhat actually the old way does not work. I actually found that I have asbsolutely no draw, but when I first used the test light method I thought I did.
The issue with the light is when you first connect one end of the test light to basttery post and other end to disconnected wire, the truck gets a connection to the ECU but the test light (or multimeter) does not have enough current so the ECU never gets past the delay and just keeps trying - thus the test light will remain on perm making it appear as a draw is happening. That is why the test light never went out even after I pulled ever fuse.
The proper method is to run a jumper wire (on aligator clips) when the battery post and the disconnected wire - this creates the connection allowing the ECU to activate and after 20 seconds shutdown. At this point you connect the test light (or multimeter) to the battery post too and the other end to the disconnected wire - now you disconnect the jumper. If the test light goes on you have draw, or if the muti reads more than .035ma you have draw. At this point you can open the door to test and you will see the test light (or multi) turn on and then off again in 20 seconds.
Anyway, this method showed that I actually have no draw at all (just like GM told me when they tested for draw when the truck was still under warranty).
The odd thing is my battery always slowly draw down and once weak the H2 alternator never gets it back up even on long highway trips? When the battery is weak I need to charge it with an external charger. When this is done, the battery is strong for 3 months but eventually starts to weaken and again the alternator never gets it back.
Could the issue be that I have a cheap Costco battery that is actually slightly less cold-cranking amps than the original? I've read that the factory battery was just on the border of being adequate - perhaps my 'smaller' battery is being used more than the alternator can feed it?
Thanks
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