My sisters 99 24v is having some dead battery issues. I hooked up a clamp meter to the positive clump of wires off of the batteries. With everything off, doors closed etc there was about .8 or .9 of an amp draw. I pulled every fuse and relay in both locations with no change in amps. The only reason I ask this is because just recently her radio started staying on, even with the ignition off and key in her hand. Not sure what is going on there, but when I pull the radio fuse, I only drop about .2 of an amp. So I put it back in............. she needs her tunes. LOL Fired truck up after boosting for about 20 minutes and everything seems fine. Alt was putting out about 80 amps and charging @ 14+ volts. The batteries were new NAPA ones that I put in about 4 months ago.

 

How about when you pull the IOD (Ignition off drain) fuse? Do you get the same 1 amp draw?

I had a similar thing happen.....certain components in the truck draw power for a certain amount of time after the truck is shutoff. If I remember right I had the same 800 mA-1 amp draw. This will sound strange becuase it went away and I never did figure out what the problem was.

I think the stereo staying on is a good place to start. Is it a replacement ?

 

Guess I lied. I did not pull the IOD fuse. It had the little holder on it like the airbag fuses which I did not pull either. But I really did pull every other fuse and relay! Thought the fuse must be pretty important with that funky guard on it. And I had no idea what IOD was anyways. The weird part is the .2 of an amp drop when I pull the radio fuse. Is that enough of a amp draw for me to get my hooves into the wiring? GAH I hate just about everything electrical in vehicles. I know enough to screw things up! LOL

 

You bet 1 amp is enough. it may take overnight, but yes.

is 1gal/min enough to fill a swimming pool?

you bet it's enough, it just will take a while.

 

It sure is enough. if your batterys are brand new and holding a full charge they have a 135min reserve capcity. Thats how long they will last with a 25amp load I think? so each battery with a 1 amp discharge in a "perfect world" would last like 56hours or something. Of course that will take your battery down to nothing and you need alot more then that to turn it over.

 

If I leave the XM radio (old Delphi Roady) turned on when I leave my truck (old Delphi Roady), the battery will die in about 3 or 4 days. If I leave it turned off, the batteries will last at least 2 weeks (longest it's ever sat without driving)

sounds like something in the headunit is bad... you may just want to swap it out with something aftermarket... you can get the kits at various places that make the install a 30 minutes or less job.

-J

 

John, unplug the light in the engine bay, and check the amp draw AFTER the truck has been sitting for an hour or so. I think there are some things that suck juice after the truck is turned off. Also, make sure the light in the glove box is turning off (although theres no way that could draw an amp).

 

I guess I will keep looking a little more into this...... Thanks for the tips guys.

 

Did the radio just start staying on?

 

Is it a Quad Cab? My '99 had a similar discharge issue that turned out to be the seatbelt timer control module. It allows the seat mounted seatbelts to be pulled out with the ignition switch off. The timer energizes the seatbelts for 30 minutes from when the engine is switched off, or the door is closed. Do a search here for more info. You can replace it for $120+ from the dealer, or you can splice the "always hot" power wire with the "switched hot" wire. This won't allow the seatbelts to be pulled out with the ignition off, but saves a lot of money for a little inconvenience.

 

Mike,

Good tip on the seatbelt!

Scott,

Yes, about a week ago her radio started staying on. Even with ignition off and key in hand. The radio will play, but if you turn radio off, the time display will stilll stay on. Factory original cassette stereo. Checked my 04.5 and nothing was showing and on my 98 I was getting about a .1 which could just be a fluke because the meter might be so out of range. It is a fluke meter set on the 200 amp setting. Nothing lower.........

 

Thats what I was talking about but I couldnt remember the details. Awesome info Mike.

 

Sounds like something has gone bad... stereos get a constant hot line, and a ignition switched line. They use that signal to tell them to turn on/off, but their power source is the constant hot.

Either the stereo is getting the wrong signal (e.g. bad ignition switch, short in a circuit to a live wire that gives power to the ign-on lead on the stereo), or something has gone internally so it doesn't turn itself off.

 

It's possible that tune player is causing the power down not to work. This happened to my son's Suburban. It killed 3 batteries before the service tech figured it out. You may have to unplug the "tune player" when leaving the truck.

 

If you have a factory trailer tow plug on the back of your truck there is a hot wire in there that does not get switched off with the truck (for charging the trailer battery). If the plug has filled with mud etc. and got wet it may be one of the causes. (although, one would think one of those fuses you pulled would have stopped that....)