I am trying to figure out why my batteries are being drained to the point where the truck will not start. Happened twice in the past week. First time it happened I found a loose battery connection and assumed that was the problem. Charged the batteries and cleaned and retightened the four battery connections. Thought all was well but same thing happened after leaving it two days. Second time the batteries were not as badly drained, but truck would not start and there was loud clicking every couple of seconds coming from somewhere in the in cab fuse panel. Did not stop till I disconnected both batteries.

Checked in and around the in cab fuse box and GEM and there are no obvious signs of water leakage. As there has been lots of rain lately I ran water from the garden hose along the windshield and no water showed up in the cab.

I did some searching of previous threads and think the following is the steps to take to track down the problem.

1. Recharge the batteries
2. Leave them disconnected overnight or a couple of nights to see if they both hold a charge. Check them with a multimeter to see the voltage. If the voltage is not up to snuff, replace the batteries.
3. Reconnect the batteries, start the truck and measure the voltage from post to post on the batteries while the truck is running. If vol
4. Turn truck off and check to see what the level of draw down on the batteries. If there is, go through the process of removing fuses or relays from both panels until the drawdown stops.
5. If removing fuses or relays from both the fuse panels does not stop the drain, disconnect the alternator to see if that could be the source of the problem.
5. Post the results and see if anyone has any suggestions or solutions.

Does this make sense as the steps to follow?

Any other suggestions or comments?

Glenn

 

Where'd you get your batteries? I woke up to a truck that wouldn't start this morning. Saw on my gauge that the V was down to 9 or 9.5V. Had my wife jump me (yeah, yeah -- that's too easy), and drove to AutoZone. Since I bought DuraLast Golds, they had a 3 year free replacement. Bought 'em two years ago, so I walked out with two brand new ones. Unfortunately, the same part number I had is rated for 25 less cold-cranking amps, and 15 less reserve capacity amps. At lest they were free...

 

Can add, Pull the radio, possibly.. I thought i read someplace the radio has been known to cause problems with drains.

 

Did you clean the tops of the batteries as well? I've had some that would get corrosion on the tops and be drained over night after a rain. I would aslo check for corrosion on the connections at the alternator.

And yes the steps are good guidelines to follow assuming you have a multimeter.

 

Alternator Diode is another, to add to the possibility list. Can get the alternator checked at autozone/Napa.

 

I was thinking it could also be a bad diode in the voltage regulator.

Doubleubar,

Step 5 in your post should be moved up to a higher order. Something to check sooner then pulling all the fuses.

 

My new gremiln is th reason my batteries were drained. I described it in my :battery woes thread. Freaking vent fan was running all by it's self on high which is where the switch was set. But no key in the truck.

Still doing it but I drove in to work anyway and turned the fan off when I got out. I will find the relay and give it a good whack.

My son has a 2000 Focus and the relays do the same thing. possessed I tell you.

 

That could be the culprit or one of several. You can pull fuses for some accessories you know you don't need to see if you can do a quick fix (radio, cab lights, etc.). If that solves your problem, you have at least found a general area too look. When you shut your truck down for the night take out all the fuses you did the night before, except leave one more in that the previous night. The next morning check your battery voltages to see if you dropped a good amount. Do this until you have all the fuses back in and have found your gremlin.

How old are you batteries? Do they have the correct rating? Are all your connections clean (baking soda and water with a nylon toothbrush will do the trick)? Is your ground strap in good condition with a solid and clean connection?

I have heard that your battery voltage should not go below 10V when cranking (if you go below, you have little reserve capacity and is an indicator of old age or bad/damaged cells). You will need a second person to crank while you measure or set it up to see from the cab. When you get up in the morning check the battery voltage before you do anything. You should be hovering around 12VDC (give or take). After you get it started, you should be around 14VDC (industry standard is 14.4VDC) which will show that not only is the alternator working correctly and charging your batteries, but the the voltage regulator is operating correctly too.

One last thought for checking batteries. Disconnect both batteries and measure them individually. They should be around 12VDC (give or take) and pretty close to the same reading. If one is noticeably higher then you have one good and one bad battery. These rigs need both batteries in good condition to fire up these big blocks. The starter has a high current draw to provide the power necessary to turn over these engines. Not to mention that the battery is also supplying your glow plugs at the same time.

It seems like a lot but your electrical system is very important. If you have damage to one part of the system, it can stress the rest of the system too and cause more damage. Bad batteries can cause the alternator to work harder and it dies trying. Bad batteries also make the starter work harder with less than required current. Bad alternator/voltage regulator improperly charges the batteries and this can reduce capacity and possible damage cells.

IMHO you can never be too careful when it comes the the electrical system. Just my .02

 

Thanks for all the suggestions.

Batteries were not new when I bought the truck last year. I will replace them but would like to find out if there is more than one problem before putting the new ones in.

To disconnect the alternator, is it a matter of removing the plug at the back of the alternator? Or do you have to disconnect the plug and any other wires? Does the plug just pull out?

I did clean all the battery posts and cable connections. I coated them with Noalox after reading in the threads that may be a way to limit corrosion.

I will do the checks and see what happens. Could take a while as I am heading out of town for a few days and the truck will be sitting dead at home.

Glenn

 

Push in on the detent and that 2 wire plug on alt will pull out. Also disconnect the large cable. Pull the boot back and you will see the nut. 10mm I think.

 

The easiest way to check the alternator is to touch it in the morning, after the engine has completely cooled. If the alternator is warm to the the touch, it is drainiing your battery. The alternator should be as cool as your engine block.

My DB Electrical alternator, that was 4 months old, had the same problem last week. Bad diode.

 

Easy way to check current draw..

Disconnect one battery completely
disconnect pos. term on other battery,using a test light,connect one end to the battery post and the other to the pos.terminal.

If the light is on,you have a draw.
disconnect the alt wires,if the light goes out,the alt is bad.

second,pull the radio fuse,light goes out,there is your draw.

( I mention those 2 specifically because they have been most sources for draw in my experience)

Using the light as a "guide",remove/reinstall fuses one at a time until the light goes out.When it does,that circuit has the draw.


Yes you will have a small draw constantly from electronic control devices,radio memory etc.usually they would be milli amp draws and probably not enough to light the test light.(or extremely dim at the least)

If you have a DVOM,you can use that as well,possibly even read milliamps if functional.

 

My guess is your batteries need to be replaced. For whatever reason my truck eats batteries. The weirdest stuff happens each time. It used to bug me, but now I just try and believe that my truck is just trying to keep me on my toes. My truck is on it's 6th pair of batteries. They got replaced in Dec '01, Oct '03, Jan '06, Jan '08 and July '09. I paid for the '03 batteries at Ford so the '06 set was free under warranty. The '08 set was pro-rated and the '09 set was free again.

When the batteries are a little weak, your truck will crank over very easily but there won't be enough juice to fire your injectors. They need AC voltage, so the batteries need to be pretty strong for the voltage conversion.

When they start to get dead cells, the truck will crank slowly, but still may start. Then you may notice weird stuff like the AC isn't very cold or your 4x4 hubs won't engage. This is because the vacuum pump can't produce enough vacuum to operate all the stuff. If your AC blows through the defroster vents only....check your vacuum pump to see how many volts are present.

Check your voltage after you replace the batteries. With luck, you may find everything back to normal.

 

That's unusual that batteries would fail that much. I can see maybe getting a bad battery here and there (which would screw up the pair), but 5 replacements in 8 years ! Have you checked to make sure your alternator is operating normally (14.4VDC at around 1200 rpm IIRC)? I think the accessories are at full rated capacity around 1100-1200rpm.

A chronic electrical problem can affect the rest of the system (bad batteries reduce alternator lifetime and vice versa).

Just my .02

 

Yeah, I thought the same thing. Turns out it's pretty common here in Phoenix. We have 16 7.3 Powerstrokes in our fleet at work. The batteries need to be changed every 2 or 3 years. If you look at the replacement dates, I normally get about 24 months before I have the change out the pair. This last set only lasted 18 months though... so that was odd. I take the truck to Ford each time the batteries need to be changed. Each time I have the dealer check the entire electrical system to see if everything is in spec. Each time they say the system is charging normally and there aren't any unusual issues. Still running the original alternator because the dealer says it checks out perfectly.

2 years later I am back to see them for more batteries.
Weird. Maybe the 118 degree summers have something to do with it....