14 replies to this topic

[yukonjackxl]

we have a 2004 gmc yukon xl with 30,000 miles on it. if we leave it for 1.5-2 days it won 't start in the morning. i have found some tsb about the hvac control head not going to sleep, and the blower motor continuing to run after the key is removed. i'm not sure these are the issues. i have put 3 batteries in this truck, i am ready to trade it in due to ther frustrations. i am afraid my wafe and kids are going to be stranded somewhere with a dead battery.

does anyone know of other issues or reasons this would happen?

any help would be great.

thanks in advanced,

Lee

[BigSilver]

Somewhere in the labyrinth of wires, there is a parasitic current drain. I had a similar situation with my 1985 Suburban. Turned out to be the electric door lock's resettable fuse. It was draining the battery, because the door lock switch was electrostaticaly fused at the contacts in the on position. This is a common occurance with the electric door lock mechanisms. The above may be affecting your Suburban.
Good luck.

[BigSilver]

Another possibility is that your Suburban is suffering from multiple corroded ground points, that are supposed to complete the many electrical circuits. Had this occurrence on a 2003 Suburban. As a result, it ate a couple of batteries, until the ground points were cleaned up. What was happening here, is that the battery was not being charged up.

Three problematic ground point locations on the 2003 Suburban, maybe similar to your 2004, are:
1. front left (driver's) side of chassis, just behind the bumper, near the left tow hook, if equipped; in line with bumper's cut-out for a vent or light.

2. Left chassis side just behind the left front wheel well, at the body/chassis mount point.

3. On the back of the engine block, between it and the firewall. (For this one I just attached a new ground cable to the engine at a conveniently accessible place, and routed it to the negative battery terminal.

Attached Files

•  ground_points110.jpg   149.65KB   32 downloads

[yukonjackxl]

well after some messing around today. i pulled the positive battery terminal and installed a digital amp meter in series with the battery and the positive cable. after all the equipment/lights shutdown, there is a 167 ma draw on the battery. i have read some bulletins from GM that says it could be the HVAC control head staying "awake". however this would only account for 60-70 ma based on that bulletin. i also read the the typical draw should be 7-9 ma. i have also seen a bulletin that says it's the blower motor relay, it has "micro welded" contacts and continue to run after the key is removed. they also say that it is possible to see a higher ma draw for 2 to 3 hours after the vehicle is shutdown. maybe my next move will have to be to set a meter on it for a few hours and see what the draw is. i think my meter has an auto power off function so that it doesn't kill the battery in the meter.... may have to find a different meter.

i will also try to get it on a lift and check those ground points, thanks for the tip.

[bill190]

You could have one person watch the amp meter while another starts pulling fuses. See what makes a major dent in the amperage draw or if it is many things combined.

Probably best to replace each fuse after pulling it so you don't get a pile of fuses and can't remember which went where.

In many vehicles I've owned, there are empty slots with no fuse.... Actually now that I think about this, probably a good idea to take a picture of the fuses before pulling any just in case!

[ScottieBoy]

Try looking at night to see if any lights are staying on. I once had a problem in a previous vehicle with the battery draining and I ended up seeing a sliver of light coming from the glove box one night. The glove box light was staying on. It could be something as simple as that. You have to check everything you can think of. And do like Bill said and check fuses to see which one is pulling the draw.

[yukonjackxl]

well i'm one step ahead of you two. we started doing that last night. thats how we found the 170 ma draw. i pulled every fuse under the hood and nothing changed. then it got to dark to continue, i need to do the same routine with the fuse panel at the drivers side door.

today is rain all day so, i don't think i'll be checking the rusty ground points. thats a job for a dry day.

[elcamino]

There was problem in the Cadillac CTS where this would happen. It involved the interior light fader switch in that if the switch was set to too close to the always on interior lights, then it would draw down the battery but never light the interior lights to allow you to know the switch was ON.

Check of something like that....or some other switch stuck on ON.

btw - The solution was to not park the slider to close to the full on position..

Do you have ANY installed accessory that did not come as part of the vehicle from GMC? Alarm or DVD or anything? I know some who had a ham radio in his truck that was killing his battery even though it was professional installed and dismissed as the problem by more than one expert. Not until some small dealer just disconnected to test it that did they discover is was the ham radio after all.

Edited by elcamino, 29 March 2009 - 08:45 AM.

[yukonjackxl]

there is a ham radio installed, but it is only powered when the key is in the on position. just for that reason. it does have an aftermarket alram/remote starter installed. i think that is going to be my next move. investigate the wiring on that unit, and see what the draw is from that unit. perhaps there is something wrong with it.

it is a strange situation though, it has been fine for 2+ years, just the last 3-4 months is when we started having this problem. strangely enough it was after the 4 wheel drive control module went bad. i replaced it and had it flashed, then the 4x4 was back to normal. but it seems when that module failed is when we started having the issue with the battery.

[yukonjackxl]

well after some investigating, i found that it is the alarm that is the culprit. there is a relay that provides +12 volts when the dorrs open to trigger the alarm. this relay is powered all the time the doors are closed. the relay is tied to a gray w/ black trace right under the sterring column. when the doors open, it is ground when the doors are closed which in turn energizes the relay. when the dor open, the gray w/ black goes positive, then the relay changes state, and supplies +12 volts to the module of the alarm circuit.

i now need to come up with a new way to operate the door trigger.

thank for everyones help.

i will still put it on a lift and check the ground points that were mentioned. lots of salt around here, with lots of corrosion potential.

Lee

[bill190]

So if you disconnect the "gray w/ black" wire from the relay, then close your doors, then the draw from the battery stops?

And if your reconnect the "gray w/ black" wire to the relay, and close your doors, then the draw from the battery reappears?

[yukonjackxl]

bill190, you are correct.

i made it easier, i just pulled the relay out of the base.

but basically the same thing.

[ScottieBoy]

Thats totally installed wrong. I've been installing alarms and remote starters for over 10 years, even worked in 3 different shops over the years. First of all, the alarm should have a negative input so you wouldn't need a relay to trigger the alarm by opening the doors(any decent alarm would). Second, the installer was too lazy to do it right. That gray/black wire is the domelight wire. The installer obviously cut corners by just using that domelight wire to trigger a relay, and then have the relay trigger the alarm. But then the domelight would not trigger the alarm if you had that domelight bypass button pressed. The CORRECT way would be to find all five door triggers (4 doors and the rear hatch) and tie all five together with diodes so they don't have any backfeed into each other. Then once you have all five tied to one wire, that one wire should trigger the door trigger on the alarm. This way EVERY time a door is opened the alarm will trigger regardless of whether you have the domelight turned off or not. If you are interested in doing this right, I can mail you some diodes (if you pay for shipping) and detailed instructions on how to wire this up. You obviously have enough skill to diagnose the problem to that point, so wiring up the diodes shouldn't be too complicated for you. Or you could probably find some diodes at a local radio shack for less than a buck a piece. But first you have to find the door trigger wire on your alarm and definitely find out whether it is neg or positive. If possible, see if you can find the main brain or black box and see what brand and model it is. Or you can look up the FCC id# on your remote on google and possibly find out that way. Another thing, did you have this installed somewhere, or was on the truck when you purchased it? If you had it put on, the shop should warranty it (at least any reputable shop would), I know every shop I've ever dealt with gave a litetime warranty on anything they installed. They warrantied the install, but not the actual product, and in your case its a problem with the install.

[ScottieBoy]

Heres the info I just found on how to corectly wire the door triggers.


Door Trigger see notes - see notes
Notes: The driver door trigger is gray/black at the driver door module in the door. The RF door trigger is black/white at the passenger door module in the door. The LR door trigger is lt. blue/black, pin A3, and the RR is lt. green/black, pin A2, they are in the purple plug at the BCM. Trunk/Hatch Pin pink/black - BCM, purple plug, pin A1
Use all five wires and diode isolate each.


The gray/black driver's door trigger they are referring to is NOT the same gray/black positive domelight wire. You will actually have to go inside the two front doors to get at the door trigger wires, and run a wire thru the door boot from under the dash to inside the door. This explains why the installer was too lazy to do it right, its a pain to have to run a wire into each front door.

[bill190]

Yes diodes are a good thing!

These only allow electricity to flow one direction. Sort of like a one way street.

A diode looks like this...




The top drawing is the way a diode would look in an electrical diagram or factory wiring diagram.

The middle picture is what a diode looks like. You can get these at an electronics store. Do NOT get what is called a "zener" diode! (These only turn on at a certain voltage.)

Then the bottom arrow shows how these are a "one way street" with electricity only flowing one direction.

For electricity to flow through the diode, the "band" would need to be connected to the negative side or ground. This is easy to remember because the band looks like a "-" or negative.

Same thing with the drawing. The "|" part on the right would go to negative.

(An LED as is used in some flashlights is also a diode! A "Light Emitting Diode".
Try connecting it backwards and notice it will not work! Then try a regular bulb - works either way.)

Below are a couple of simple diagrams to illustrate how a diode can "block" electricity.

On both diagrams there is +12 volts and - or ground, two light bulbs, and two switches.

On the first diagram, if you turn on either switch, both lights will turn on.

On the second diagram with a diode only allowing one way "traffic", the left switch will turn on both lights, but the switch on the right will only turn on the light on the right!

First diagram...



Second diagram...



The diode above will not allow the ground (-) to flow to the left when the right switch is turned on, but will allow ground (-) to flow to the right when the left switch is turned on. Thus the switch on the left turns on both lights and the switch on the right only turns on the light on the right.

Edited by bill190, 30 March 2009 - 07:06 PM.