Battery drain - looking for help and ideas

Igor Sakhnov

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Couple of months back I installed new ADD front bumper with Rigid lights. Was really happy with the results, lights connected to AUX with DRL spliced to come on automatically, all bells and whistles.
At some point I switched back to my other car and left truck seating in the garage for about 10 days. Weekends comes, I try to start it and nothing. Battery is fully dead. I think it was about 4V reading if i remember correctly. I jump start and discover the battery does not hold the charge any more, get a new one and test to see what it going on. Locking the car and waiting couple minutes - observe a drain of about .3A. Unplug all new lights, camera and radar - still about .3A drainage with the car locked and settled into a sleep mode. I have not tried removing ADD and the two things that come to mind even remotely related - relocation of the cruise control unit and the lower active shutters motor that is no longer utilized.
I tried doing the fuse game by pulling fuse at a time and looking for drain to stop - no luck. At some point I ran out of time to debug, installed batterytender to keep it plugged in at night, locked the truck for the night (as this appears to lower expected drain as well) and settled to wait for more time to troubleshoot. Pattern of going to / from work and son's school worked fine with no problems.
Had to travel and my wife drove the truck and she calls me one day not able to start. Battery is dead again even that she plugs it into batterytender every night.
Looking at the forum, saw a thread with the reference to the front cabby in the central console having light on when cabby is open (the one with USBs and bluelight). There is a big difference in behavior - it is always closed when I drive and open when wife drives so that is one of the culprits. I went further, locked myself in the truck and peered through the cable whole under the lid of the central console - bin light was also on. So, this gives me two lights that seem to be always on in the truck, not sure how mush would they drain and I will test by removing the bulbs tomorrow.
Any other ideas on the source of the drain, or the ways to troubleshot it?
Thanks!
 
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smurfslayer

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I don't recall who, but a user here reported a '17 or '18 maybe, battery drain and it ended up being the sync module. After shutdown, some time later the sync console would restart. I believe they caught it by using a camera in the cab.
 

FordTechOne

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0.3A/300 milliamps is a very significant battery drain; a small light bulb will not draw that much.

Since it started happening after installing the new lights, begin there. Pull the fuses for the upfitter switches first. If the draw is still present, remove circuits that are spliced into the factory wiring, do a battery disconnect/reconnect, and see if the draw is still there.

From your other posts, you have a dash cam as well?
 
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Igor Sakhnov

Igor Sakhnov

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0.3A/300 milliamps is a very significant battery drain; a small light bulb will not draw that much.

Since it started happening after installing the new lights, begin there. Pull the fuses for the upfitter switches first. If the draw is still present, remove circuits that are spliced into the factory wiring, do a battery disconnect/reconnect, and see if the draw is still there.

From your other posts, you have a dash cam as well?
Yep, removed main wiring for lights and harness for the embers, dashcam and radar. Still the same. Removed all of the engine bay fuses one by one, pulling PCM made the only difference if I remember correctly. Will be doing another pass this weekends.
Another interesting observation, there was a "washer fluid low" warning both times preceding the problems. She would first start fine but with the warning. Stop the car later and fail to start from there.
Another interesting note - car is off for the last 14 hours and battery still reads 12.5x V. Yesterday, it was fully charged (green light on the tender), 20 minutes drive with a stop of another 20 minutes and then failure to start. Strange.
 
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Igor Sakhnov

Igor Sakhnov

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Spent more time this weekend with a bit more patience. 0.3A was not correct. Truck settles into 0.095A draw in about 30 minutes. This is still 3x the norm, but I highly doubt this would kill a new battery in couple of months on a daily driver truck.
Anyone could measure the baseline drainage on the gen2 truck with all bells and whistles like remote start etc.?
 
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Igor Sakhnov

Igor Sakhnov

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Media light - cabby light in front of the shifter? Both cabby and central console go dark once truck settles into the sleep mode.
 

Ruger

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I had a similar problem, and like you it had to do with lights. I have auxiliary back-up lights on my truck, and they're just plugged into the trailer plug. And that worked fine for years until I noted an anomalous draw on the battery. It turned out to be an accumulation of dust in the trailer plug. Evidently there was enough dust to bridge between the electrical contacts and form a ground. All it took to solve the problem was some compressed air. Just FYI.
 
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Igor Sakhnov

Igor Sakhnov

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I had a similar problem, and like you it had to do with lights. I have auxiliary back-up lights on my truck, and they're just plugged into the trailer plug. And that worked fine for years until I noted an anomalous draw on the battery. It turned out to be an accumulation of dust in the trailer plug. Evidently there was enough dust to bridge between the electrical contacts and form a ground. All it took to solve the problem was some compressed air. Just FYI.
Thanks! By now I had disconnected everything newly plugged as part of the change done :(
 
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