robp823 Posted December 11, 2010 Share Posted December 11, 2010 Have a 96 f-250.Batteries go dead overnight.Batteries were replaced by customer.He had it hooked up to a tester at advance and brought me in the paper.Its says Drain test 24.66A.Investigate power drains that could affect battery life and performance.I hooked up my meter and set to milliamps.My meter says 17.08 and keeps fluctuating.I started pulling all the fuses under dash.The only one that affected the draw was when i pulled the fuse for the door chime.And it n only came down an amp and a half.Same under hood pulled all of them and the only one it came down for was the 50 amp maxi for the instrument panel fuses.Only came down a little still pulling like 14.34 amps.Im stumped.Am i supposed to test the drain off both batteries???Or just one.I should have my meter set to milliamps correct????Any help appreciated. Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted December 11, 2010 Share Posted December 11, 2010 24.66 Amps is significant. That high of a draw will blow the internal fuses in your multimeter as most have 10A or less fuses inside them. (by the way Lowe's carries replacement fuses for your multimeter at a fraction of that your tool monger charges) I would disconnect one battery completely and only use one for testing You do know the proper procedure for making your connections and module time-out right? Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted December 11, 2010 Share Posted December 11, 2010 Disconnect your alt and see if the drain is there, it's common for the regulator to short causing a drain. A small DC amp clamp is really handy for this problem, about $50 at Sears. Good Luck! Quote Link to comment Share on other sites More sharing options...
robp823 Posted December 11, 2010 Author Share Posted December 11, 2010 Well when that test was run for the 24 amps the truck was running.Thats the way the machine tested it.Now that i think about it Bruce that makes me steer more toward the alt.My multimeter is hooked up i hooked it up to regular amps first and it was like 3/4 of an amp.Didnt want to blow my milli fuse.When i switched it to milli Thats when i had like the 17 to 18 milli amps.I disconnected the negative cable from the battery and ran my leads inline from the negative post to the terminal connector.Is that what your talking about Keith???Bruce ill try disconecting the alt tommarow.Whats a normal parasitic draw considered? Quote Link to comment Share on other sites More sharing options...
Mikill Posted December 12, 2010 Share Posted December 12, 2010 I'm with Bruce. I have seen a few alternators draining the batteries. Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted December 12, 2010 Share Posted December 12, 2010 A 1996 truck does not have that much in the way of high tech energy consuming electronics like todays cars. Do you have a meter such as this one? If so (it can be any meter, just has to have a seperate amp lead hook up) set the dial to the amps setting (red arrow) don't dick around with milliamps, that's a complete waste of time on a truck this old. Put the black lead in the normal ground connection and put the red lead in the amps connection (green arrow). NOTE: AS SOON AS AMP DRAW TESTING IS COMPLETE MOVE THE RED LEAD BACK TO THE POSITIVE CONNECTION OR YOU WILL BLOW THE FUSE IN METER IF HOOKED ACROSS THE BATTERY TERMINALS Now you need to isolate the batteries due to it having two. In this case disconnect both battery grounds and hook your meter up as pictured to the passenger battery. As soon as you make the connection, look at the meter reading it should be next to nothing. If it indeed is 20 amps or more break the connection. My meter is rated to read 15 amps and I have seen 30 amps briefly when an abs pump shorted out. If the reading is low, turn the park lights on. This should bump the reading to around 6 amps and park lights should illuminate. This just verifies your hooked up correctly. The factory spec. is 20 milliamps and your meter will read 0.02 amps. Continentals were allowed 50 milliamps due to the onset of multiplexing and advancing technology. Quote Link to comment Share on other sites More sharing options...
robp823 Posted December 12, 2010 Author Share Posted December 12, 2010 I have a blue point meter It reads amps and milliamps. Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted December 12, 2010 Share Posted December 12, 2010 I have a blue point meter It reads amps and milliamps. I have a Radio Shack (now 'The Source' in Canada) meter and it, too, reads in mA and Amps. IIRC the mA scale is up to 100 mA with a 500 mA fuse. Thge 10 amp scale is 10 amps with a 10 amp fuse. FWIW, I use "slow blow" fuses. Interestingly... I purchased two different sets of leads for my DMM. Each set alone cost more than the meter. It isn't "the tool" that matters... it is how you use it and interpret the readings that will decide the repair. Performing a parasitic draw test isn't rocket science - but you do need your wits about you. I'm sorry if this sounds brutal but (as Kieth points out) - a 24 amp reading isn't going to happen on most DMMs and it really isn't going to happen on an mA scale. To compound the concern, offering bogus info when seeking help is going to make matters worse.... we despartely need to be on the same page if we are to offer/ask for help. Back when I was on the fire department, I would encourage members to "play with their toys". I do that with our techs as well. With the shit you have in your junk drawer, you should be able to build a simple circuit... Use that simple circuit to gain the familiarity you need with your DMM. In the online WSM for 1996, there is a crude outline for parasitic draw testing in section 14-00. FWIW, I see this test as being done wrong more than done right. Word to the wise... before embarking on this test, be absolutely sure that the batteries and charging system are not the cause for concern. Now that we are nearing the middle of winter, it is important to ensure that the block heater is working - our guys check to see if it blows a regular breaker but not to see if it blows a GFCI breaker... 1 Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted December 13, 2010 Share Posted December 13, 2010 He had it hooked up to a tester at advance and brought me in the paper.Its says Drain test 24.66A.Investigate power drains that could affect battery life and performance.I hooked up my meter and set to milliamps.My meter says 17.08 and keeps fluctuating. Is it 17ma or 17amps? 17ma would be a perfectly normal drain. Hook up your meter like Brad says below, in series between the negative post and negative cable with the other battery disconnected. Set your meter on amps and take your reading. Open the door or turn on the interior light to verify your meter is connected correctly, the reading should increase by 1-2 amps. Originally Posted By: robp823 Well when that test was run for the 24 amps the truck was running. HUH? You CAN'T do a parasitic draw with the truck running, it can only be done engine off! If they got 24A running, that was the charge rate going into the batteries. As for normal parasitic drains, Brad is dead on. 20ma (.020a) is considered normal on a low end vehicle and 50ma (.050a) might be towards the upper range for a high end vehicle. If you're a math whiz you can actually take the amp hour rating of the battery, divide it into the parasitic draw and come up with a theoretical time the battery would last. I think I came up with 9 months the last time I did the math on a car, but I don't remember the numbers I used. With the size of 950's I'm sure you'd get well over a year.... Quote Link to comment Share on other sites More sharing options...
robp823 Posted December 14, 2010 Author Share Posted December 14, 2010 Ok sorry about the confusion the parasitic draw test was not run while the truck was running.The little slip they printed out from advance auto says 24.66A.Im not seeming to get much draw when i switch it to amps,but then again i didnt have the other battery disconnected.I wont be working on this rig again until this weekend.With all this great advise from everyone ill go at it with a full head of steam and get my results up and what i found ASAP.Thanks again. Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted December 16, 2010 Share Posted December 16, 2010 Ok sorry about the confusion the parasitic draw test was not run while the truck was running.The little slip they printed out from advance auto says 24.66A.Im not seeming to get much draw when i switch it to amps,but then again i didnt have the other battery disconnected.I wont be working on this rig again until this weekend.With all this great advise from everyone ill go at it with a full head of steam and get my results up and what i found ASAP.Thanks again. I can only suggest that you take the little slip from Advance Auto and send it to the "round file". They couldn't fix it (or so it seems) so their info isn't much use to you... They have given you the number 24.66... but what does this represent? You cannot do a parasitic draw test accurately if you are supplying current flow fron "another" source. In this case, it sounds like it may be the second battery. I just went through a similar situation with an apprentice. He failed to isolate the second battery (along with an alarming proclivity of removing postive cables first)... A word to apprentices everywhere.... if you pretend to know what you are doing, I will pretend to think that you know what you are doing..... In dual battery installations, the ground is "generally" a common circuit. We do need to ensure that our parasitic draw testing includes the positive taps from BOTH batteries. Electrical testing is, by far, the most misunderstood things we do. Sadly, once we grasp the basic ideas, it becomes close to the simplest of things we do. Quote Link to comment Share on other sites More sharing options...
robp823 Posted December 19, 2010 Author Share Posted December 19, 2010 Ok had the truck on a good long ride.About 2 hours.Did exactly what all of you guys said.Disconnected the Left side battery.Put my meter in line with the negatve cable and the negative terminal on the right side battery.Turned my meter to amps.After letting the truck sit for 5 minutes,I only had .020 amps.I opened the door just to make sure i was connected correctly and had a 1.50 to 2 amp draw.Shut the door and it went away.Now im puzzled.This morning i had a battery charger hooked up to it along with my 80 k2500 hooked up with it to get it going.It took a while as it is about 30 degrees where im at.I did notice that while i was trying to get it going that when you let the glow plugs cycle that seems to kill the batteries instantly.So instead of letting them cycle i just would turn the truck over and it seemed to crank normal and fast.Im going back outside now to test the glow plug relay.I also think im going to do a voltage drop on the starter cable for the hell of it.Mr. Warman i am pretty green in this field still and im not taking any of anyones comment as being a prick just soaking it all up.Again all the input from everyone is appreciated and this is a very good learning expirience. Quote Link to comment Share on other sites More sharing options...
robp823 Posted December 19, 2010 Author Share Posted December 19, 2010 Ok when i went back out there i never took my meter out of series and found it pulling 1.009 amps.When i wiggled around the lead that plugs into my meter for amps i noticed the amps fluctuate so there was another problem right there with my meter.Any way got that fixed.The first thing i did was unplug the alternator,the positive cable and all the connectors no change.Then i went back to square one pulling fuses leaving the fuses that i pulled out, out .The second fuse i pulled the draw went away down to 0.020 amps.It was for the door chime but i think there is other circuits on there.Gotta go to the EVTM i think. Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted December 20, 2010 Share Posted December 20, 2010 Hmmm, one thing I will do in setting up a parasitic drain test to diagnose battery drains is open both front doors then close both door latches to the closed position and leave the doors open. THis way you can access fuse panes and modules as necessary without opening the door latches and triggering courtesy lamps and security modules and so forth and so on etcetra etcetra... Quote Link to comment Share on other sites More sharing options...
robp823 Posted December 20, 2010 Author Share Posted December 20, 2010 Well thats a good point.I didnt do that but with that fuse pulled the draw went all the way down to 0.004 amps. Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted December 20, 2010 Share Posted December 20, 2010 You gotta quit fooling around with those dead batteries. If they wont charge make the customer pony up for some new ones. If you charge the batteries and or jump them off and they wont even cycle the glow plugs, then everything else is gonna be a waste of time. Get some fresh batteries in this thing before going any further. Quote Link to comment Share on other sites More sharing options...
robp823 Posted December 20, 2010 Author Share Posted December 20, 2010 They are fresh batteries Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted December 20, 2010 Share Posted December 20, 2010 Yes, but have they been trashed by repeatedly charging them and running them dead? You can RUIN brand new batteries inside of a few days doing this. Most standard automotive batteries (not deep cycle) can only withstand being run dead about 3 times before major plate sulphation takes place. Also, the quality of the battery charger and how long they've been charged enters in- many times if you leave a charger on a battery overnight, it ruins the batteries. Do you have a carbon pile load tester? If not, you NEED one to properly diagnose this problem. Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted December 21, 2010 Share Posted December 21, 2010 Direct result of improper battery charging: Quote Link to comment Share on other sites More sharing options...
robp823 Posted December 21, 2010 Author Share Posted December 21, 2010 wow Quote Link to comment Share on other sites More sharing options...
Fordracer Posted December 22, 2010 Share Posted December 22, 2010 Another quick tip for checking for a current draw is to check the voltage drop across the fuses instead of pulling them. The one causing the draw will show a voltage drop. Quote Link to comment Share on other sites More sharing options...
Fredsvt Posted December 22, 2010 Share Posted December 22, 2010 Hey Keith, Doesn't the old '96 have conventional door jamb switches in the A pillar, not latch switches? Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted December 22, 2010 Share Posted December 22, 2010 Ahyup. We saw the first GEM in Super Duty trucks in 1999 models that appeared in 1998 along with door ajar switches in the door latches. Good to point that out as we don't want to confuse anyone. Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted December 22, 2010 Share Posted December 22, 2010 Another quick tip for checking for a current draw is to check the voltage drop across the fuses instead of pulling them. The one causing the draw will show a voltage drop. If you have a significant ( as in readable ) voltage drop across a fuse, I think you'll find you have a cause for concern. A voltage drop indicates a resistance. Besides, I'm already using my DMMs ampmeter feature to indicate my parasitic draw severity. We would use a voltmeter more to find why a load ISN'T functioning... rather than why it IS. (Warning.... the preceding statement needs to be taken in context and treated with some respect). Electrical testing is simple and easy... for some strange reason, the human psyche finds (and fulfills) some obscure need to complicate matters. Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted December 22, 2010 Share Posted December 22, 2010 Electrical testing is simple and easy. It's simple and easy for those who understand electricity. Unfortunately, most technicians do not. Merry Christmas! Quote Link to comment Share on other sites More sharing options...
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