Mysterious battery drain

Corrosion causes many problems. We just had another member with what appeared to be a Start Problem only to find corrosion on the Positive Wire under the jacketing.

Its good practice to clean up any contacts etc and apply a little NoAlox to all electrical connections anywhere you see them including the Grounds.

Stoked on the good news.

 

Well, I'm back with some issues. I let the truck sit since Friday evening and on Sunday night, it was completely dead. I took my battery tester out there and it was around 11v and 8% SOC. I jump started the truck and it fired up. Drove it for about 45 min and rested and it tested good. The ONLY thing I can think of is since I installed the new door checks, my doors are pretty stiff and really take some effort to close. There is a possibility that I didn't close one all the way and it killed the battery. It has never drained the battery this fast so I am not sure. I also finally setup some alarms on the Torque app for voltage. During a 30 min drive, it probably goes off 10-15 times for volts to high. I have it set at anything above 14.5v to alarm me and it goes off quite a bit. I did finally catch it in the act and when it does get a voltage spike, the gauge on the torque app glitches out and then catches itself again. The gauge on the dash never moves.

I am letting a friend borrow it right now so I dropped it off at her house last night around 7:30pm. I took my battery tester over there this morning at 5:30am and it said it was good but only had 12.5v and 78% SOC so it dropped quite a bit in less than 12 hours. At this point, I am not sure what to do. I just ordered an alternator for it but if that doesn't fix it, I am lost and will have to take it in.

 

Are you leaving the OBDII dongle plugged in all the time?

If yes, have you tried removing the dongle while the truck isn't running to see if it continues? I've heard dozens of stories about OBDII sensors causing a wild variety of wacky issues with vehicles, from starting to charging/discharging to ... you name it.

Just curious!

 

Yes and no. When I was letting it sit for multiple days, I was unplugging. After I thought I 'fixed' the issue, I have been leaving it plugged in. The dongle crossed my mind a few times that it was some how causing a spike in voltage but every time I have done a parasitic draw test, the dongle hasn't been suspect. It has never died off this quick though which leads me to believe that I left a door open... either way, it's pretty frustrating. Before I could leave it at least 5-7 days but this time, it died in two.

 

Welp, I think I have it narrowed down once again. I got the truck back from my friend last night and decided to check it out. First draw test showed 0.60ma! It has never been that high so I went back and started over by pulling fuses. The only fuse that dropped it significantly was the 7.5a fuse for the OBD port. It dropped it down to 0.44ma which is still high. I removed the OBD dongle, put the fuse back in and it stayed at 0.44ma. That little sucker was drawing 0.16ma on it's own! It was still high but no other fuses reduced the amp draw. I then remembered my aux fuse box for my accessories. The circuit for my power invertor was drawing power. I remember driving sometime last week and hearing a weird beep. Long story short, somehow my tool kit in the backseat hit the 'on' switch for the power invertor so it had been running this whole time... .

So between the OBDII dongle and the power invertor, it was drawing 0.42ma. I now have it down to 0.06-0.08. My light bars are drawing about .005 each so maybe the relays are bad or that is normal, not sure. @shifty`, you were spot on about the OBDII dongle. That thing draws quite a bit of power for what it is being plugged in. I read some reviews on google and it looks all of those types of dongle's will draw power if left connected. I did order another brand to see if my voltage is actually spiking or it is because of the OBDII dongle going bad. My voltmeter on the Torque app glitches out and sometimes will say volts are as high as 18v!

 

Yup. I think you'll find many of them - if not all - have adverse effects from leaving them plugged in all the time. Not just battery drain and reduced battery life, things like ... Failed starts. Rough starts. Loose or awkward idle. Power fluctuations. I even read one case on another forum where someone's ABS would randomly engage if the dongle was plugged in overnight. The minute they got rid of the dongle, all symptoms went away.

 

I've read similar as well. I really like the it but it may not be worth it in the end.