Look for a bad battery to ground connection. Corrosion/loose/whatever. I wonder if the alternator is indeed putting out, put the juice isn't making it back to the battery.
In another forum I am in, the door courtesy light switches stick, or the doors sag with age and fail to "open" the circuit, sometimes intermittently. Maybe the liftgate, considering you are at your cottage when it happens? Try shutting off the courtesy lights entirely for a few months.
Keep us posted.

 

Thanks, John V. I'll have to wait till AM to check the connections, but I can turn off the interior lights easy enough. I once had a '68 Impala that would just quit driving along if I hit a big bump. I'd coast to the shoulder and fiddle with the cables until I got a good connection. Eventually got tired of that and put out a few bucks for new cables. Money was pretty tight in those days.

PS, Greetings to Connecticut. I grew up there. In fact that was when I had the aforementioned Impala -- it was my second car. Wish I still had it.

 

Another thing that you can do is disconnect the negative battery cable, then put a test light between the cable and the battery. Then start pulling fuses until the light goes out.
Use a standard incandescent light, and do this with the doors CLOSED and the key out of the ignition.

 

Very good idea!

Also, you can get an inexpensive digital voltmeter from Harbor Freight for around 10 bucks--and it has an amperage scale--I believe up to 10A. That will show the exact current leakage regardless of how minute.

Also, remember that the alternator B+ lead is constantly connected to the battery, but isolated by the diode packs. If one diode is leaking, that could cause a problem.

Not sure about jeep alternators, but a Delco I once owned had an internal voltage regulator, and the input to that was always connected, with was isolated by circuitry. However, when that went bad, it took the battery down in a week!

Regardless, we all are looking for the end all fix!

 

To me still sounds like alternator
May not be putting out full voltage when under load

 

Must be one of those elusive intermittent problems, since they could find no fault after supposedly going through all the diagnostic procedures. Odd also that they reset the engine DTC, it came back again, but they never revealed any OBD codes to you.

Without a multimeter and OBDII gauge there's very little you can do.

FYI, here's the (partial)diagnostic areas in the factory service manual for a system that will not maintain a charge. The system being the battery, starting system, and charging system.....all are inter related.

1. Incorrect battery size.
2. Dirty battery connections. This has fouled me up before. They can look clean, but an invisible oxidation layer can create INTERMITTENT connection.
3. ignition off excessive draw: normal draw- these are the max draw: Radio-1-3 mil amps, Audio Power Amp 1 mil amp, PCM .95 mil amp, Cabin Control Module CCN .44 mil amp. Total ignition off draw should be below 35 mil amps.
4. Bad battery. Sometimes a new battery is bad.
5. Bad starting system
6. Bad Charging system
7. Load exceeds output of charging system (aftermarket stereo?).

These things are the tip of the iceberg without going into all the test procedures. And, it is cut and paste. I'm not an expert on this stuff....just a tinkerer.

Good luck.

 

Bad connection/corrosion was my problem.

 

Well, a couple hundred dollars later my local mechanic found the problem.

So, should anyone be looking for a grounding problem, in my case it was the wires running under the passenger side kick plate (inside rocker panel). It deceived the computer into thinking the ignition was still on and so it ran down the battery.

This is why we have the forum: to share our problems and solutions. Maybe I can save someone else a pile of money if they look there first. At 187,000 miles, my Patriot may be having problems that others will be having as they age.

 

Well, a couple hundred dollars later my local mechanic found the problem.

So, should anyone be looking for a grounding problem, in my case it was the wires running under the passenger side kick plate (inside rocker panel). It deceived the computer into thinking the ignition was still on and so it ran down the battery.

This is why we have the forum: to share our problems and solutions. Maybe I can save someone else a pile of money if they look there first. At 187,000 miles, my Patriot may be having problems that others will be having as they age.

i replaced my battery and alternator n still have the same problem. my battery light is still on and my alternator isn't charging my battery, Someone told me my internal computer system is fried and needs replacing and reprogramed ( voltage regulator) did u have this problem? i have a 2009 Jeep Patriot 2.0 engine.

 

More info on this. My local mechanic found a problem, but not the problem. The problem persisted and gradually became more frequent until it happened every time I turned it off. It would run down in 6 hours even. Took it to my dealer (in whom I have great faith -- they're good) and they found a bad spot in the wiring harness, under the battery/relay area. My guess is that seven NH winters got to the lower part of the harness. Several wires are corroded in the same area and the damage is causing the computer to think the engine is still running so the computer never shuts down. That was what the local guy found, he just didn't find the correct reason why.

So friendly advice to others, check that area on your wiring harness and be sure its well protected.

At 190,000 miles, Ignatz is in otherwise great shape, so I'm putting out the $$ to get the little guy fixed. Plan is to get him through the winter, or who knows how long. I know its a gamble on my part, but I think the odds are in my favor. Frankly I'd rather put out $1000 than $20,000. With the lifetime warranty on engine and tranny, I'm willing to spend a few buck for incidentals.

 

Hey Ignatz, I'm having a similar issue. IOD (ignition off draw) circuit is draning my battery overnight. Like you, it seems the CPU think my car is not turned off.

What did the dealer do to fix the problem? Is it something I could check/do myself?

Note: One of my battery terminal is half broken and waiting for a replacement, could it be a problem? Something like that but clean split

 

I'll post my answer on this thread and on the other thread you started.

First a word of caution: your problem may not be identical to mine. It does sound similar so the big reason for my posting the above thread was to give others with a similar problem a place to start looking. I figure my mileage is higher than most and I'll be hitting problems before others do; figuring these vehicles are virtually identical, a weak spot on one will probably show up on others.

My solution was not cheap, but I feel it was worth the money. It was near $1200 to replace the engine wiring harness. Once they figured out where to look (directly below the battery) the corrosion was obvious.

There was no practical way to gerry-rig it except to carry a spare battery, which I did while I was still trying to figure out the cause. A spare battery is not a permanent solution, because gradually more and more things will start failing. My service adviser felt the problems would be more of a nuisance than an actual safety issue, but predicted the ABS brakes might stop working and I'd be getting false warning lights on the dash (that was already happening on 2 counts).

If you've seen inside the harness, there's a million wires in that cable and it would be a needle-in-a-haystack to isolate the offending wires, and it would be a short wait for yet another wire to corrode. I debated putting out the money, but at 190,000 the trade-in value was nil -- and to me it was still an otherwise reliable vehicle. To boot, I already had invested in a new battery when the problem first started, and my alternator checked out OK, so I went ahead and did the work. No regrets on that decision.

You know best how you feel about your Patriot. If its been good to you and you like it, I'd say spend the money. If you've had it up to here with repairs, it might be a good time to make a change. Let your conscience be your guide, but you'd be better off trading in than selling privately because if you sell it privately, the new owner is going to come back and punch you in the nose. If you trade it, the vehicle will get wholesaled a couple times before before anyone has to cope with the problem, and it will probably be a dealer who has the expertise to find the cause and fix it.

 

Oh, I doubt a cracked terminal clamp could cause a draw, but there's a slender chance it could affect the power outflow -- you might find everything working, but unable to turn the starter. Pardon any redundancy, but somewhere in this thread or another similar thread I mentioned a '68 Chevy I had with a bad battery cable. Visually it looked fine, but all it would take was a hard pot-hole or a set of RR tracks to cut all the power: lights out, dead car. I'd get out and fiddle with the cable till I got a connection again, and all would be well for a few days or a few miles. This was really a problem as it got chillier or in the rain, etc.

But in answer to you question, I doubt that's your problem, but mayyy-be . . . Electrical problems are frustrating.

 

For the people having battery drain issues, there is a product on the market you wire into your main battery lines and will cut all power to the vehicle before the battery goes completely dead. Could be a life saver until you find the issue causing the battery drain.

 

I thought about that, but doesn't that reset everything electronic? Then again, I guess a dead battery would do the same. I bought one of those battery boosters for $75. It got me through a troubled month till the problem could be diagnosed and now I've got it should it ever be needed in the future.

 

Don't know if this actually helps?

I was having draining problems with a new high cranking amp battery.
The draining seems to have stopped when -

- ALL accessories were turned off, zero'd.
- especially fan, htr, interior light console attenuator on steering column.

• I make sure I lock the door from the FOB instead of from the door so the 'aid' headlights don't turn on after closing the door.
• I did remove the battery cables and wire brush cleaned everything, including the battery poles.
• I used a rubber mallet to securely tap in the cable clamps flush to the battery.
• I applied dielectric grease on the exposed cable surfaces.

I'll take it into the garage so they can do a battery drain test.

 

PS, when it comes to electrical problems, I tend to go to a bona fide dealer because even though they charge more, they are more likely to have experience with similar problems since all they work on all day is Jeeps. A local mechanic may know a little something about many cars, but Jeep dealers are devoted to only one brand and should know a lot about it.