2 Day Battery Drain... Out of Ideas

[nickelghandi]

Hey all,

I have been fighting and actively troubleshooting this since September and I am getting tired of it. My battery is dying in 2 days if my Pathfinder is not driven. As long as I drive it once every 24-36 hours it will be fine, but as it approaches 36-48 hours, it is noticeably weaker. Once it passes that 48 hour mark it is basically dead and if it hasn't been driven at all in 48 hours, the keyless entry, lights, etc. don't even work.

If I drive it every day, it will run just fine and start just fine every single time. I did so for 3 weeks straight, until I needed to use my pickup for a few days. Came back and of course, the Pathfinder was dead...

I have taken it on 200+ mile road trips and it will do fine. The battery only dies when the Pathfinder is not being driven.

Here is what I have tried:
- Testing battery - passed (Battery is new as of March
- Testing alternator - passed (Alternator is new this year and is OEM)
- Replaced alternator with another new one under warranty - no change
- Replaced battery - no change

Found THIS post from forever ago. Chuck (rest his soul) had some good things to try as he always did, and so did ARKQX33V6. I read through that thread and a few others, and followed some troubleshooting tips in them:
- Disconnected negative terminal and watched sparks - lots of sparks so something is pulling some amps - duh
- Disconnected positive terminal and connected a multi-meter set for amperes. Started pulling fuses to check for amp drop when problem fuse was found. I pulled every fuse and relay I could find and no drop in amps...

I have LED headlights and HID foglights as well as an aftermarket Clarion head unit and a PAC audio interface. I also have some off-road driving lights haphazardly wired in. I have no sub or extra amp or anything like that.

- I tore out all of the wiring for the off-road lights because it needs redone properly anyway - no change
- I unplugged both foglights - no change
- I unplugged both headlights - no change
- I unplugged all HVAC controls and Stereo equipment - no change

I swapped the interior lights to LEDs a couple years ago (you know.. for the horsepower ) and I noticed that the one in the main part of the cabin stayed on very dim all the time. I always figured there was a tiny bit of current going through that system so it can talk to the door switches and that because the LED requires so little power it just lit up a little bit. I never had any drain previously. Regardless, I tore them out too and even unplugged the entire assemblies but... no change.

I have read a little bit about the starter being the culprit by drawing too much current at startup and then the truck not being driven enough to charge the battery back up, but it seems more like a bad ground somewhere to me. Also, my commute is nearly 30 miles one way highway so I would think that is plenty of high speed time for the alternator to charge the battery.

I am out of ideas, and opening myself up to any suggestions people may have.

[Rockwood]

Absolutely everything in the truck is powered from the fusebox under the hood behind the battery. If you go to pages EL-12, 13, and 14 of the service manual it shows all the fuses and fusible links in that box. Fuses are single S shaped lines, fusible links are double S shaped lines. Pull those one by one and you will find the circuit pulling the load.

The alternator output cable connects to that box, and would be a current draw if you had a bad alternator diode, but it sounds like you have covered that already. You can disconnect the alternator output cable if you want to as a double check.

That should get you onto the bad circuit.

[EdBwoy]

Might you have a towing kit and harness as well? OEM?

Thanks for linking to that thread btw. I try to update the titles with the solutions to help others doing searches in the future.

[nickelghandi]

Rockwood:

I have tried most of what you have suggested already, but left the alternator out. I will check it again and make sure all bolts are tight and wires are in good shape. I figured I must not have pulled them all or else I would have found it.

EdBwoy:

I do have a towing kit and if by harness you mean plug on the back then yes I do. And actually I did use the Pathfinder to tow a trailer about a month before I noticed these problems. I had trouble getting the trailer lights to work due to corrosion on the plugs. I wire brushed them, but if something came loose and shorted then I bet I would see some drain.

I am sure there are relays, fuses, and links associated with that system along the line as well. I will check it out today and report back what I find. Hopefully I can find some reference to the proper voltages on the towing hitch wiring somewhere.

[EdBwoy]

RE: towing. By harness I meant the whole wiring kit, plug to plug.

I'd check the ground. I had hardwired my harness, piggyback-ing on the taillight for ground as well as that's what I figured the OEM to be. It worked well for 2 or so years then suddenly I couldn't get a good ground, and my headlight fuse would pop whenever I connected anything to the trailer plug... then it'd be fine for the trip after replacing the fuse.
Eventually we traced the problem and grounded a jumper wire to the tow brace itself. The grounding issue had been minor enough that the trailer lights lit very dim, but big enough to drain the battery slowly when hooked to a trailer.

[atraudes]

This page is an excellent resource for finding parasitic drains. The Voltage-Drop Battery Drain Test in particular sounds like it could help.

The LEDs staying dimly lit in the car for a while even after being powered off is super common. If you buy CANBUS-compatible (or usually even just higher quality) components, it won't happen. Except for it being distracting while driving at night it's not detrimental and highly unlikely to be the cause of your battery drain (unless they're staying on ALL the time). The common remedy for this is to hook up a resistor in parallel with the LED. The resistor will quickly shed any residual electricity by generating heat. I personally used 100 Ohm 1 watt resistors as they generated very little heat; they barely got warm.



Good luck!

[Kev90]

To echo others and your research you have a parasitic loss. And finding the culprit is sometimes really tough. I have seen where the light on a sunvisor would never turn off when closed, or light in glovebox wouldn't turn off. I also had a friends escape where the starter when stopped at certain times would completely drain the battery in an hour. Replacing the starter fixed the escape but not after 2 months of scratching my head and replacing alternator, multiple batteries, disconnecting every possible fuse, lightbulb, and disconnecting the battery whenever stopped. As a stop gap until you figure the culprit you can buy a battery disconnect switch so you don't destroy your battery. One thing is based on the time it takes to drain the battery is it is only pulling a small amount of power.

[nickelghandi]

I apologize for the lack of updates. I bought a house and was mid-move so didn't have time to troubleshoot. The battery also died again and I have not had the time to go and charge it up. I usually drive this vehicle every day, but I own other vehicles I can use in the mean time. I disconnected both of the terminals for now. This time it died overnight in the course of about 9 hours. I am beginning to suspect the starter because I started it to move it in the driveway, and it started fine without any problem and then about 9 hours later it was totally dead. The power door locks won't even work. Previously, I had been starting it and driving it at least 15 miles on the highway before shutoff which is probably enough time at high speed for it to get charged back up even if the starter is pulling huge current. Now my commute is only about 6 miles and it is all low speed country roads.

Atraudes, the light is so dimly lit that it can only be seen if looking directly at it. It gives basically no light to the interior of the vehicle. It more of just glows. Honestly, I kind of like the effect. It is like those emergency lights in planes. I always know where the light is because of it, but it doesn't affect drivability. I have wired resistors into my rear turn signals to eliminate hyperflashing with LEDs so I am familiar with the process. Before anyone asks, I did remove those and the entire tail light assemblies to see and it did not affect the drain.

EdBwoy, I do not think it is the towing harness. I borrowed my dad's tester for towing electronics and it passed everything. Current seems only to flow when it is supposed to. It is supposed to tell you if there is any current flowing and has little LEDs that illuminate. It is not a fancy device, but it seems to have done the job. I did not inspect the ground connection or any additional relays, but I am now leaning away from the towing harness.

Kev90, I think you may be right about the starter. Everything else I have checked has been fine so far.
There is a local shop that did my transmission last year when it went out. I think I will just pay them to troubleshoot the starter. This same shop did the alternator so they can check that too. It should still be under warranty. I am tired of fooling around with it in the cold lol. I will update this thread as soon as I know something new so we can add "SOLVED" to the title. Thanks for the suggestions.

[nickelghandi]

I have not totally solved the issue just yet, however I have discovered a slight humming noise coming from the engine bay with the engine shut off. Initially I thought that was the fuel cap making noise, but I opened that and left the truck sit for 3 days and it is still present. It also goes away when I disconnect the battery. Whatever it is, I think it is what is causing my drain. I still cannot seem to isolate it, but at least I know the general location; that being the engine bay... It seems to be to the left side, but it is so faint it could be from anywhere and reverberating/resonating in the left side.


I will update again when I know more, but I am open to suggestions. What might be making a humming noise?

[EdBwoy]

I'm thinking solenoids and actuators in general: AC compressor clutch, variable intake solenoids, power steering, evap solenoids attached to the intake, throttle position sensor and electric throttle... just disconnect what you can access and see if the humming stops.

EDIT:
I just thought about this too - headlight ballasts and (if applicable) the motors that tilt the lights up and down

[nickelghandi]

Alright, I finally have an answer!

After extensive (read expensive) testing, the shop has finally determined that the alternator diode is what is causing the drain. This is the 2nd alternator I have had in the past year and this particular one was installed by this shop. They are warrantying the part and labor so no cost there and they are actually only going to charge me one hour of labor for diagnosis, and installing a new wiper arm transmission, even though it took them like 5 for the diagnosis. I know the owner of this place... played soccer with his son like 10 years ago, refereed soccer with him and his son.. So I would imagine that there is a little bit of family/friends discount going on here and my experience might not be typical.

I am not that familiar with alternator diagnosis, but I know there are more extensive tests that can be done than just hooking it up to a machine to see if it is charging. Just because it is charging does not mean it is working properly.

In response to EdBwoy, I don't have headlight aiming motors, but any of the other mentioned items could have easily been buzzing due to AC current dumping into the system.

Thank you everyone for the responses and suggestions. I am so glad my Pathfinder will be back on the road (or off of it) soon!

[barnaclebob]

Nice! Thanks for the update.

[QX4ME]

Yes, I'd also appreciate the update. I gave my friend my old Hyundai that has a very intermittent battery draining. I will tell him to check the alternator. Do you think it's possible to replace the diode only instead of the whole alternator?

[macgiver]

mac here,if 'n your a tinkerer and a replacement diode is available , tests w/ multimeter , and if Alt. is easily serviceable i've done it on Delco (American GM car) and many times you would consider buying all 6 diodes (they're a 3 phase winding -could be a "cluster) and higher Amp ratings may be "had" .It's "out there" thing to try . TIP = virtually ANY Alternator may be tested w/multimeter (Using "Diode" setting & double chk w/both lowest Ohms - power diodes can stand "low scale" ohms test ) .Best part - easily done on the car , BUT FIRST yo MUST disconnect battery cables (yes ,best BOTH for this) and then it's SAFE now to disconnect the OUTPUT (heavy)wire on Alternator - the "control" wire socket does'nt need to come off (better to remove - but maybe kinda unaccessable). Multimeter probes are put on output stud , other probe directly to Alt case (better than car's gnd or the block even) NEXT Do Reverse probe test - IT SHOULD READ CONDUCTVE IN ONLY ONE DIRECTION. Technically it's whats called a 3phase "full wave bridge " configuration , and when even ANY one diode "Blows " = going "Low impedance shoretd"you get that heavy parasitic draw which kills battery / Yet not enough to blow the typical "Fusible link (s) . 2/22/2018