Hello, I need some assistance figuring out what is draining my battery. I just recently picked up a 2005 Dodge Ram. After a few weeks I tried starting it up and heard that dead battery sound and noticed that the security light indicator light was on making a clicking sound. So I did a jump start and it worked for the day and the same issue happened again the next morning. So I went out and bought a new battery and everything seemed fine for about a week and now it’s happening again. I thought it might be the alternator so once it was started and running I disconnected the battery to test and see if the truck would turn off, it didn’t. I then took it to a local mechanic and we connected a meter and worked with the negative post and started pulling fuses. There was a charge being pulled until we removed fuse 51. We verified everything was turned off but have no idea what is draining from that fuse. He tested the new battery and it was showing that it was drained from the week but also noticed it was saying to replace it instead of the normal message to just charge it. So I went back to the store and returned it and now installed another new battery. I then had the mechanic test the new battery which showed good this time and then he looked at fuse 51 again and it was still showing a charge getting drained. I don’t have any special additions to it like amps just the basic radio with cd and tape player.
My first question is should there be a continuous charge coming from fuse 51 when everything is turned off? Secondly what could be draining the power? I’m out of ideas and any help would be greatly appreciated.

 

do you have a under hood lamp?

 

Yes there is an under the hood lamp. We also tried unplugging it and still were seeing a charge pull from the 51 fuse.

 

So I am just guessing fuse 51 is your cluster, under hood lamp, radio fuse. One item that can be causing a draw here, although very small, not enough to drain a battery, is your radio. It should have a constant power to it with key on or off to maintain memory like clock, preset stations, etc. First thing I would try is to remover and unplug the radio to see if this helps or corrects the issue.

If still drawing with radio and under hood lamp unplugged, next would be the cluster. Read somewhere else where a short or issue with a bulb in them can cause a parasitic draw.

Secondly, removing any battery connection with the engine running is not advisable. This was an old school way of diagnosing a bad alternator. Could cause more damage with the electronics and such in today's vehicles. A better way to check an alternator output is to check battery voltage with engine off. Then crank the engine and re measure battery voltage. If alternator is good, should see a voltage increase somewhere in the 14v and above range.

Good luck!