80 milliamp battery drain on a 1999 Ford F250 super duty 6.8l v10 4x4
I pulled fuses in the interior fuse box until I saw the 80 milliamp drain went to 0. It was the 15A fuse in location 15 of the fuse box. This fuse affects the GEM, PCM, ABS Module, Shift Interlock, and Speed Control. How do I go about disconnecting one by one to see which component has the short. I know where the gem is located but it controls a few things but I don't know exactly what it controls on my year and model. Gems on other year and model control different things. Can you help me on how to proceed to find what is causing the battery drain?
If it doesn't control the alternator, then I shouldn't bother to do a load test on it
Nothing to do with control. If your alternator is faulty, then it won't charge up the battery between starts.
My original post is about a battery draw and I found it to be on circuit 15. My user manual says what that fuse affects and I listed them in the original post. It mentioned the pcm abs gem and 2 other things.if the alternator isn't associated with this circuit, there is no need to test it for the drain on the battery. If the battery is new and fully charged and I don't start the truck for 4 days and then the truck doesn't have enough charge to crank the engine, what would that have to do with a faulty alternator not being able to charge the battery. That comes into play while driving the car and the alternator not working properly to charge the battery to over let's say 12.6 volts so while driving and using the lights, ac, radio and other things, that the alternator would keep the battery charged.
Scotty always says, "start with the simple things first". As MMJ suggests, you should load test the battery and check the alternator. Please do both. These are the best initial tests. Here's why (1)The new battery could read adequate voltage but still fail a load test. Creating your starting problem. (2) Test your alternator, it could be bad or weak. Creating your starting problem.
Any decent, honest mechanic would give you this exact advice.
Thanks Hixster and MountainManJoe. I will take your advice on getting the battery checked out and the alternator load tested.
One last thing I want to say is that I don't know much about cars or trucks and came here asking for help. My question was not what might be causing my truck not to crank but, how can I find what is causing the 80 milliamp draw on my battery that is associated with circuit 15 on the internal fuse box on a 1999 ford f250 superduty.
Is your battery actually going dead? Do you have problems starting the truck? There is always some quiescent current going to keep the clock and electronics going.
80mA is not much. It's the equivalent of four indicator LED's, and it shouldn't drain the battery before it's able to charge up again. If my math is right, 80mA would take around 40 days to completely drain a battery, if it was non-stop.
The truck barely cranks after 4 days. I was told anything over 50 milliamps is an issue so you are right that there is always some current going to keep things going like the clock and other little things but that draw may be 25 milliamps or atlleast under 50 milliamps.
The 80 milliamps that I have is constant but goes to zero when the 15A fuse on location 15 in the interior fuse box is removed.
there is not a big difference between 50mA and 80mA (the 50mA number varies depending who you ask too), and definitely shouldn't drain the battery in 4 days. Have you had your battery & alternator load tested?
I haven't had the alternator load tested. The battery is a new battery, 2 months old. I have 2 other vehicles that I drive so I am not starting up the truck for over a week sometimes two. If I knew what the gem controls, I can test those components. Like I said in my first post, I don't know what components the gem on my make, model and year controls. If it doesn't control the alternator, then I shouldn't bother to do a load test on it. But if I knew that it does, then I would certainly test the alternator of. So I guess I can assume the gem does control the alternator and so I will have it tested
I don't know exactly what it controls on my year and model.
These cost only $35 and contain electrical diagrams in addition to repair information. Well worth the money.
Thanks for the Haynes Repair manual info.
I will test the alternator....it's probably the cause especially if it is on that circuit
My original post is about a battery draw and I found it to be on circuit 15
as I already explained, 80mA is not enough to drain a healthy battery in 4 days.
.if the alternator isn't associated with this circuit, there is no need to test it for the drain on the battery.
I never suggested testing it for drain. I said load test. You can get this done for free at a battery dealer or parts store.
the truck doesn't have enough charge to crank the engine, what would that have to do with a faulty alternator
Again... the alternator charges the battery. No charge = no crank
I'm not crazy about repeating myself. I've given you my advice and you seem to know better, so best of luck.
how can I find what is causing the 80 milliamp draw on my battery that is associated with circuit 15 on the internal fuse box on a 1999 ford f250 superduty.
The only way I can think of would be to physically cut the power to each device connected to that fuse until the draw goes away. As has already been said though that should not be enough current to quickly draw down a healthy battery.
Thanks Chuck for addressing my question on the approach to finding what is causing the battery draw. And it very well be a faulty alternator "if" the alternator is on circuit 15 in the internal fuse box. The suggested Haynes repair manual would tell me the devices connected to that circuit. Thanks again