Help --Elec Meltdown

Yesterday morning when I went to start my 2007, the auto lock would not work.  I opened with the key and the elec sys was dead. No lights, dinging...nothing.  I turned the key and that is when the sys went nuts.  Battery indicator showed full charge but everything started flashing.  The radio, windshield wipers, dash lights etc started blinking/flashing/off then on.  Tried to crank and weird sounds every where.  The fuse box was clicking, some sound maker was trying to make sound but it was a very low freq, not the usual ding.

I hooked up the battery charger, and it showed charged, so I tried to start it again and then the break-in alarm went off, and every thing started to flash/blink again. Battery level then showed only 8-9 volts.  Check the battery charger and it was fluctuating between charged and sending mega amps....I removed the fuse box two times and then went to google.  When I came back the radio started working , things stopped flashing/blinking...So I tried starting and it started.  But every warning (I think everyone) was showing up even one that I had never seen,  Engine Power Reduced, in addition to the Service, Stability, Traction, Tire etc.  Also the stability said it was off and the off/on button didnt work.  I drove it around the block and let it run while I went to google again. 

when I came back only the Engine Power Reduced warning was showing.  I hooked my code reader and got a P0606 and cleared it.

The truck ran fine after that all day yesterday, and this morning it is just fine....

What is the verdict...maybe the mega fuse, or a faulty neg battery cable....?

It has had similar issues before (not the flashing/blinking of everything an all the warnings) but what would appear to be a Totally dead battery and after jumping/charging all was fine..... 

Dead Battery or Faulty battery
Bad connection @ battery.
BAd battery cables
BAd grounds wires @ block, etc.

Critter chewed some wires under fuse box

Check battery cables first
Get battery Load tested second

Have the battery "LOAD TESTED" first.

And as mentioned above, check your battery cable connections, as well.

Testing with the readout from a battery charger means nothing.

Most auto parts stores will do this for you for free.

Ask specifically for a LOAD TEST.

A battery that has a dead or dying cell or cells can cause all kinds of weird electrical problems.

We recently had a bad battery cause the entire cluster to stop working on my mother's Tahoe.

Replaced the battery with a new one and everything is now right with the world.

Load test the battery and go from there.

Thanks guys,

I should have said that this is my 3rd battery in as many years.....both of previous batteries pass load test, but after replacing the battery the problem was slowed....meaning much longer between episodes .

I will have the 8 month old battery load tested....but if it is the battery , what is causing such high failure rates with the batteries?

Have you had the AV since new? Has it been in a flood or accident? Have you or a previous owner added anything electrical to the AV such as lights, alarm system, stereo gear etc.? Does your Av set for long periods of time or is it a daily driver? Are the batteries high quality with equal or better then GM power ratings? Doe your drive on the highway enough to fully charge the batteries or do you make a lot of short low speed stop and go trips?

This is my 2nd Av, both were new.  It is a 2007 with 144k miles, most of those were pre 2008, when I retired.  It is driven about everyday, almost entirely inter-city, less than 5 mile trips.  No flooding, but it was rear-ended, that bent the trailer hitch bar, no other known damage.

The last battery was from an auto supply house, not the best, but not the low end either.  The cranking and cold cranking ratings are to spec....not sure if there are other ratings that I should be concerned with.

I have this "feeling" (no hard data--just gut) that it is related to weather and/or my wife.

It seems to happen after a change in weather...especially rain..but this last time it happened without any rain, but it was the day after my wife drove it and cold front had just come thru.  So this is the 8-10th time of the "dead battery syndrome" in the past 3 years (I think that the first time was about 3 yrs ago)......I am going to guess that 1/2 or more I can sorta recall rain or wife....or both.

Most were very "clean" just recharge and start......the last couple were weird. Flashing, blinking and strange alarm buzzers (tones that I have never heard...the frequency of the sound was much much lower and sounded like they were being made by a defect old time horn)  And the CD player was making sounds of rapid recycling/changing of CDs  There were relay activation (clicking off and on) sounds in the fuse box....and the the battery charger had rapid fluctuation of amp draw and then would stop and settle on very little draw, until I used the key fob to activate the door locks or horn....and then rapid fluctuation of the battery charge amp draw  would resume for a few seconds and then either settle to a low draw or major charge draw....

After a few minutes (15-20) things seemed to settle down and the radio would come on and play (prior to that no elec switches seemed to work, although I wasn't very methodical in a diagnostic protocol)  I do remember trying to turn on interior lights and nothing.but the horn would honk when i pressed the steering wheel switch

Any other thoughts......my gut says faulty relay or ground (the weather factor thing) and  when (not if) it happens again, what would be a solid diagnostic protocol??

thanks for your time and support!!!   

I have a 2011 AVY with similar problems.  Door Locks clicking like machine guns, radio going off and on, all kinds of warnings displaying, instrument cluster turning off; etc. It's in the dealer shop now and the dealer called and says it bad battery cables.  Told them to replace them ($569). 

I sure hope this solves the issues.  It's been intermittent for the last few months but isn't getting better by doing nothing about it!  Should find out next week.

Electrical problems are by far some of the hardest problems to solve. You don't say where you live but you did mention weather. A weak battery will fail with the first cold front of the season and each one after that. It sounds as if you don't really put enough time on your vehicle to keep your battery at full charge. First thing is to check that your charging system is putting out at least 14 volts. If not, then that needs looking at. You also stated that your battery was a spec meeting one. It's better to go up on your battery if it does not see much use, they will last longer and take more abuse. You should buy yourself a battery charger that will do a trickle charge on your battery, 2 amps or 1 1/2 amps. These chargers are cheap and will maintain your battery for years of service.
You also stated that y'all had a accident that caused damage to the rear of the vehicle, this area has a lot of small electrical wires. If one of them was smashed and just enough of the wire is making contact with metal, you have a grounded system that will weaken and drain that battery.
When I was pulling wrenches for a living, the owner of the shop seemed to love giving me all the unknown electrical jobs that came in. Wish you the best in finding your problem. Later Fairshake 

SmokeyJoe said:

I have a 2011 AVY with similar problems.  Door Locks clicking like machine guns, radio going off and on, all kinds of warnings displaying, instrument cluster turning off; etc. It's in the dealer shop now and the dealer called and says it bad battery cables.  Told them to replace them ($569). 

I sure hope this solves the issues.  It's been intermittent for the last few months but isn't getting better by doing nothing about it!  Should find out next week.

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You should tell your dealer that the copper battery cables are fine, no need to install the solid gold ones.

Wickman said:

You should tell your dealer that the copper battery cables are fine, no need to install the solid gold ones.

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Yea no crap.. They saw you coming... Should do the big three upgrade if you have this issue... Do it yourself and end up costing far less than $200.