Here is my question, but I will start off explaining why I have this question first.
Because of the birth of my daughter my truck has been sittin a lot more then usual it was about a month an a half before I felt the need to start it up and warm it up. And on doing this the motor would barely crank over ( batteries very low ). So I took both out and charged them ( 2.5 amps for 3 days )to get a nice good charge in them, plus I had the time.
Question 1. is it normal for a diesel to drain batteries in that long of time sittin?
So then I put the batteries back in the truck but before I hooked them up I put a multi meter in line with positive terminal on passenger side and noticed a draw of
.208 amps ( seems awful high to me ) so I start pullin fuses the only fuse that would make a difference was fuse 15 ( Generic Electronic Module , Powertrain Control Module, Anti-lock Brake System, Brake Shift Interlock, Speed Control ) Once this fuse was pulled the amp draw went to .049 amps Im guessing this might be normal current draw through out the charging system.
Question 2. is it normal for the Modules on Fuse 15 to draw .159 amps on its own?
Question 3. is .208 amps too much current draw?

thanks in advance for the help

 

I don't remember the draw, but the PCM does pull "keep alive" power when the truck is off.

Give us some info on your truck. Year, mods, age of batteries, some history, etc.

 

When you first hook up the power your going to see a draw for about 30 minutes.
Could be less it depends on how long the timers take to cycle off. Once you have
then all off retest and see. Don't open any doors or move the hood if you have the light
because it will restart all the timers.
How old are the batteries? Age will lower there ability to retain a charge. If the age is
getting up there (2 years) it may just be a tired battery. Take them in and have them both
load tested to see where they are at.
I don't recall what is a appropriate level of draw during the sleep time for the truck is.
You may be able to find this in some service manual. You are going to have some because
of the KAM (Keep Alive Memory) Dose pull some power all the time..
Post back what you find. Also a good place to ask would be the forum for your engine size.
Was 99 the 7.3? They have there own forum and like I said it may be a good place to ask.
But please still post back.

Sean

 

You have to wait 40 minutes from the last time ANYTHING is touched for the battery saver to time out before making any current draw measurements if you want them to be valid.

If you did not wait 40 minutes, then the readings you made are useless.

 

ProjectSHO89,
Thanks for catching that. Is that for the 7.3 or others too?
I was going by memory when I said about 30.

Sean

 

A week and a half and a dead battery? Sounds about right. I've never had a battery hold a charge longer than 2 weeks in anything with a PCM. Brand new battery or old battery.

 

Depends what year and options as far as the wait. My 99 is good to go after 30 seconds or less. Normal battery drain from pcm and radio memory is about 20 -30 Milliamps...Not 100 or 200 ma..That will drain your battery quick.. My truck can sit for a month no problem as it does sometimes in winter when we don't get snow..Its in a heated garage..I do have a monster 1000 ca battery..

 

sorry guys my truck is a 99 and the batteries are about a year old other then power windows and power locks ( no key fob ) just a standard xlt, so I wouldn't of thought that the gem would take that long to cycle

 

The things that the programmers sneak in.
I know you said only a year old but still it's a
good idea to get then load tested separately.
Then after you do that have the charging system
tested. Once they are out of the picture you can
move on to other things.

Sean