You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!
Battery drained with new battery and alternator tests good.
I have a 4cyl 87 coupe that starting sunday will not hold a charge. I charged the battery over night and drove as usual monday. Tuesday morning it was dead again jumped it and took my kid to school went to leave a couple hours later and dead again so I charged again. Put new battery in wednesday and had the alternator checked by autozone and was told it was good, so I bought a multimeter and watched a tutorial on youtube checked it myself and was good. Had my uncle double check it and was good. Went to take my kid to school thursday and it's dead again. I don't listen to the radio and haven't had to use the heat or lights so I know I'm not leaving anything on so what could kill my battery in 12 hours? Any help would be great because I'm at a dead end here.
This ad is not displayed to registered or logged-in members. Register your free account today and become a member on Mustang Forums!
Sleeper_Inc is right. If you have a DVOM, you can look up how to do a parasitic load drain test and see how much amperage is been drained from your battery when the vehicle is not running. If theres a high drain, all you do then is start pulling fuses until the load drain decreases. Once you pull that fuse you know where the short is and where to start
you can also go to advance auto parts and get a drain test , I'm sure auto-zone can do the same . a drain test is part of the full diagnostic test ,make sure they have the new hand held machine every store should have theirs by now !!!!
Just want to thank everyone that responded, I ordered a 5.0 alternator and new wiring to put in because I think the voltage regulator or (correct me if I'm wrong) alkaloid might be faulty and I want to upgrade my audio while doing body and interior work as this is my driving project, but I also agree with sleeper inc that I could have a short after some research and am going to start checking for a drain tomorrow. One more thing and let me know if I should start a new thread or it might have something to do with my current issue but this is my 1st stick shift and sometimes I try to start with the car in 1st and it won't turn over and I have to move the stick back and forth from 1st to 2nd before the car will turn over in either gear.
__________________
Car was supposed to be a winter beater/spring project now it's a fall project/pray it runs thru winter beater.
as long as the clutch is depressed all the way and the safety switch is working it should turn over in any gear (as long as the clutch is depressed). if the battery and starter are good and you have by passed the safety switch it should start in gear ~ or maybe my 1979 didn't have a safety switch ??? can't remember did not work anyway i could start it in gear , clutch cable broke had to drive it to the shop with no clutch ( the memories
can't wait to have a 5 speed again)
it sounds like parasitic drain. but did you have the battery on a micro vat? also if you had a bad regulator the alt wont charge the battery. i had one that was faulty and was grounding to chassis preventing the alt from doing its job.
the recommended amp draw test is a good idea as well. this will pinpoint what circuit is draining your battery. if it is killing it overnight it is somerthing big.
also have you checked your battery for leaks? if the bat has a lot of contamimation ontop of it you can have a static discharge which will kill it too. just food for thought. most of these tests are low to no cost if you have basic tools and some way to get the battery to a local pep boys or equivalent.
Got the alternator figured out. The alternator was pulling power while the car was off. I found a way to keep the battery charged till I got the new alternator just pulled the positive cable off. The alternator was pulling like 12.20 and when I disconnected it the reading went down to 0.05. Thanks for the help everybody.
__________________
Car was supposed to be a winter beater/spring project now it's a fall project/pray it runs thru winter beater.
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. Ford® is a registered trademark of the Ford Motor Company
Battery drained with new battery and alternator tests good.
