Uhhh electrical whine things go boom?

[onebigburb]

Ok so sit down grab some popcorn going to a long one. I was wiring in my Dakota digital e-fan controller In which took the better part of the day. With the ignition on being flipped on and off fan being cycled on and off ect... you get the point draining the battery. So by the end of the day I was close to getting the stock ect sensor tricked into what I wanted to see from it. Then this electrical whine started it was ear piercing. OPPPSSS where did I go wrong was I getting feed back somewhere noticed stereo screen had lines in it like a t.v. from the 80's. I shut ignition off and unplugged all my e-fan stuff and turned it back on no noise at first. Then here came again this time the abs light came on and said service brakes WT* is going on? Turned ignition off unplugged battary waited and plugged in turned ignition on this time noise was instant. I noticed that the service 4wd light was off this time only check engine. That's when it hit dim lights, DEAD BATTERY. Ok I just bought a new battery 2 days ago this is the first time I have used it. So first of all does this dead battery whine/brake freak thing happen to you guys too? When I got the battery 2 days ago I thought I had a parasitic drain so I did a parasitic test. There was an old 8 ga. wire under hood from previous owner no idea where it went most likely a sub setup. So I pulled the 60 amp. fuse in it and never replaced it. With it out When I first hook up my meter I see 3.5 amp. for about 10-30sec. then drops to 15milamps. So I should be fine on the parasitic drain. I have this same battery in my suburban I have left the stereo on full blast 24hrs. partying in a field and truck still starts. So what is it about the trailblazers and draining so much juice? Yes this truck has EVERY OPTION + some. However really is dual battery only fix to this situation? Is there something I'm not seeing? O and its 900cca wet cell battery. The guy who designed these trucks electrical system should be kicked in the chone`s REAL HARD!

[HARDTRAILZ]

I can leave my radio-cd-subs-amp and led under lights on overnight, plus get in and out of truck with interiors going on and off when getting stuff or in a cooler and have zero issues with my battery dying and have great starting on first crank after.

Seems you have a self-inflicted issue and want to blame the truck or engineer.

[Trail X]

Did a new battery fix your issues?

[onebigburb]

I'm unsure how this is self inflected. truck has always seemed like it drains battery. I have battery on charger an will check tonight to see if full charge solves it. You say you leave all that stuff on however, do you have the GPS head unit or standard deck? this truck has GPS unit plus 2 t.v.'s and DVD player. A parasitic draw test should have told me if I drawing amps with truck off. So that means with truck on something is power hungry correct?

[HARDTRAILZ]

You failed to mention it has always drained a battery. Therefore given the info you shared that your efforts in putting in the e-fans killed your new battery, it would appear to be completely self-inflicted.

You also had a new battery on its first use that may not have had a full charge. Probably not the best way to use a battery by slowly trickling it down until dead on its first use.

Also the fact that no one with this platform has really seen major issues or needed a dual battery for other than camping or a fridge in the 6 or so years I have been around them tells me your situation is unique and not a typical trailblazer or electrical designer issue.

There have been some guys w parasitic drains but it was typically self-induced and with the forums help they could get it worked out by sharing all the info and not just blaming the truck or designer.

[onebigburb]

ok I thought I said that up front. apparently I did not state that so I apologize on that behalf. yes from day one the battery has seemed to run low it only ever died once while listening to stereo.

I suspected the battery was old enough it was due for one. So i put a new one in. After a day of trouble shooting things an playing with efan controller the new battery problems arose.

When thing goes a wire in trucks we always blame engineers or some one else out of frustration. Its part of the venting process. weather I am to blame or previous owner is unclear at this point. My big question is if anyone else has experienced the whine and service brake indicator upon low battery?

[HARDTRAILZ]

When my original battery went bad, it was tested at only about 450 amps or something and would not always turn the truck over, it never gave me that kind of whine or any lights on.

[TBYODA]

Cody look under the dash for odd bundles of wire and left over odds and ends. Check for any lose connection. Also check under the driver side jam (we're the door means the floor) that goes back to the fuse box under the rear driver side seat. Jason "V7guy" recently had electrical issues on his envoy that would kill the battery. Him and Matt found a left over FM transmitter that connect your phone to the radio. A ton of just twisted and electrical tape wires, some exposed to possible short

[TBYODA]

You talked about high pitch whine and that the stereo had lines on the display. The whine could be coming out of the stereo speakers maybe the previous owner had a aftermarket stereo and swapped the stock stereo back before selling with little care to the next owner. Something maybe not be hooked up right if so.

[onebigburb]

tbyoda I believe your on the right track. I have been scared of this truck since day 1 due to aftermarket electronics. I will list them as I know of them. it has stock GPS head unit however something is fishy there is 8ga. blue stereo wire headed that direction. Speakers are unknown. Trailer brake controller, DVD player, TV's in headrest. Backup camera (never seen it work).

So I got home and unhooked all my wiring just to rule it out. Apparently the battery charger got unplugged some how so battery only showed 11.5v. I figured I'd try it just to see. Hooked battery up cycled ignition on. No whine nothing everything happy. Then after o say 15sec. I could hear seat motor trying to move or something in that area an what do you know whine comes back Abs light comes on odometer says service brake. I shut truck off pulled battery and checked showed 10.5v. So we have few things going on I'm thinking.

1. tbyoda is correct wire/draw something not right.

2. If a sensor in brake circuit is cycled during the on position of switch if it see's drop in volts will it set off abs / brake ses?

[onebigburb]

So currently I plan to charge battery, pull fuse's for luxury devices I.e. stereo, seats, day light running lights and see what happens.

[Trail X]

You need to pinpoint the source of the whine if it returns. I have a periodic whine from my rear speakers only, there's a bad connection somewhere in the rear head unit wiring, and if you hit a bump in the wrong way it whines. Apparently it's a ground loop, and somewhat common in the rear seat entertainment package. Though, mines never done it with a low battery.

Low battery voltage does some really odd things with this vehicle. I had an intermittant bad battery a couple years ago and halfway tore my dash apart looking for the source before realizing what was actually wrong.

Since your problems started when your battery had a low voltage (presumably from you testing the fans too long and not charging the battery [those fans draw a TON of current]), start by rectifying that issue and see what happens after that before casing down anything else.

[onebigburb]

completely with trailx. I charged battery enough to get it up there and put it on watched it with my meter as soon as it hit 10v everything went hay wire again. So I took good battery from my truck put it in and after a few min. passed still nothing. So from this I'm gathering anything below 10v will upset these or maybe just my truck.

The whine still concerns me on another note. I was really not looking forward to ever having to dig into this trucks electronics. I guess I must now. That will have to wait for weekend. I really need to just to make sure everything is wired correct none the less. My link arms for SAS shipped this week so I'm under gun.

Now since I know this and regardless of what I find for wiring. Should I be looking into dual batt. setup? Normally I would not do that much diagnosis with install. However seeing as truck wants a lot on with just ignition on (I.e. no driver pushing buttons). looking to add c.b., rock lights, fog lights ect.. in near future. Granted most of time truck will be running and alt. will supplement.

[Trail X]

Had trouble deciphering what you wrote, but if the whine does not come back with a full battery, then don't worry about it. If a fully charged battery fixes your issues, I think you're making a mountain out of a mole hill with the dual battery idea. Simple fix, just don't run your fans without the engine running.