Hello friends!

Backstory: 2008 coupe would not start after work on the 13th. Took a jump, got the battery tested same night, good battery no problems (which is good, since I got a new one in December). Fast forward to the end of the day on the 14th, won't start, needs a jump again. Took the jump, went back to get the alternator tested and it is also good, supposedly.

Pattern I've noticed: Ever since the 15th through current, I would either run the engine all together during a break at work, or not at all and I've had zero problems since then. The difference is that I would run the electronics during breaks at work, but not turn the engine fully on. The vehicle can also however be left completely untouched over a weekend and start just fine on Monday morning for work. It has only ever needed a jump on the 13th and 14th.

I have gotten new leads for the battery that are much more tight, but I haven't been able to see the effectiveness of this yet because I still either run the engine during a break or don't turn on the electronics at all.

 

Have you been able to do any testing of the electrical system with a Digital Multi-Meter (DMM)?
When the car won't start, is the battery low on voltage?
When the vehicle is running, it the battery charging >13.8v? >14.4v?
Is there a charging fault lamp illuminated while the vehicle is running?
Once jump started, can you drive the vehicle long periods of time without issue? When an alternator is failing, the car will eventually stall when driving from lack of voltage. With a bad alternator, a quick charge and jump start will only allow the vehicle to be driven until the battery voltage diminishes to a level that's too low to sustain operation and the vehicle will stall. Duration will vary, but if the car needs jumped after sitting all day then it probably won't drive for > 30 minutes before stalling and needing another jump.

These are simple test to perform however don't rule out the alternator as there could be ripple voltage present due to failing diodes or other issues with the charging system.

My initial thought is that you have some sort of battery drain causing the issue and there are ways to test for this. It could be an aftermarket addition such as amplifiers, head unit, radar detector, etc. or something within the electrical system that isn't shutting down properly when the ignition is off.

At this point I feel replacing the alternator may be premature without additional testing and while it may fix the issue the cost and time to replace may not be worth it if the issue isn't resolved.

-Eric

 

No, I haven't been able to test it myself with a multimeter. "I don't know" is the answer to most of the rest of the questions posed. No interior indicator of a faulty battery or alternator.

Once jumped, the car will run, but I live in a small city and it's very rare to be running for longer than 15 ish minutes. Takes me less than 10 to get from work to Auto Zone, then another less than 10 from Auto Zone to my apartment.

The car however, will run in the morning. It first needed a jump on Wednesday evening and was running fine in the next morning. Then a jump Thursday evening, and just now this morning it turned on and stayed on with no problems. A failing alternator wouldn't just be affecting things in the evening, right? Maybe an intermittent battery drain triggered by God knows what? As for aftermarket additions, it's all been mechanical; catalytic converters, lowering kit, cold air intake, extended bungs. The only electrical modification, if you could even call it that, would be new LEDs for the interior ceiling lamps. Which I did pull out recently to replace with different ones, but went back to the first set. That was weeks ago.

 

I'm with Eric on not replacing the alternator as the first go to...they don't seem to be problematic on these cars...

From what you mentioned, it may be something very simple as the negative battery terminal losing contact..I'm not sure if the terminal is prone to stretching but this happened to me years ago and a few others have reported having to replace theirs as well ...there was a thread or two on this a couple of years ago IIRC a few people replaced their negative battery terminal cable....for me it would happen to me after a commute especially if it was particularly bumpy and I wouldn't notice anything until I got back in the car and went to start it and it was dead...tightening it down would pretty much fix the problem until it happened again sometimes many months later.....a few months ago I took my terminal off and reshaped it so it was super tight....hasn't happened since but I still carry a 10mil shallow socket and a 1/4 ratchet in case i need to tighten it down and i bought a negative terminal on ebay for 10 dollars I'll replace it with if it comes up again...I don't know if this is your problem but maybe its worth seeing if thats the issue..

 

Funny you should mention that, I've already had to deal with that problem lol. One day in the morning it wouldn't start, so I popped the hood and the damn cable was standing up, not even touching the battery. Stuck it back on and went about my way. That weekend I got something to fit between the terminal and cable and now that bitch doesn't move what-so-ever. Think it could still be related to the current problem?

 

I would still think its suspect given the symptoms...if it helps...in my case you could never tell visually that it was out of contact....the loss of contact was so minuscule that on occasion I could rock the car with my body weight (i'm a big guy) from the driver's seat and it would make contact again...doing that usually meant it would just happen again though...at the very least I would try to tighten it down and carry that socket and ratchet in the car in case it happen again before throwing parts at it...

last year I got a higher end diagnostic scanner for my birthday and when I did a scan of the car i could see old stored codes for a P1515 (battery current sensor) ... which I believe was triggered by these events...this isn't a code that triggers any warning lights and most code scanners cant read this code so if you really want to be sure as to what it is you could get a Nissan consult scan at the dealer to check it out but the cost may not make it worth it

 

The negative battery terminal clamp is notorious for stretching and working itself loose. I had to replace mine to solve a tricky no power condition.

In the old days, if the alternator was suspect, we would start the engine and with it running disconnect the negative battery cable. If the engine died, bad alternator. While not a proper diagnostic, it makes for a quick test.

Wasn't there some sort of mention that driving the car for really short trips does not allow for the alternator to charge the battery- some sort of "time delay?"

 

No time to be able to read response, but I will, thank you so far!

Just wanted to provide an update: No jump required today.

What I did today was start the car for a few minute throughout the day during breaks. 3-5 minutes running, three times during the day. At the end of the day no jump required and I made it home with no problems. So yeah, thoughts?

Also, are the dashboard lights supposed to get more dim when the headlights are turned on?

EDIT: Vehicle does have an aftermarket alarm system also. Can't believe I forgot about it. I'll do what I can to test the electronics if I can get my hands on a decent multimeter.

 

If the battery/alternator truly isnt the issue (which battery still seems plausible), it also sounds suspect of something causing parasitic draw (maybe the aftermarket alarm?).

 

I went all day Saturday without touching the car and it started on Sunday with no problems. At this point, it seems like merely turning on the electronics, but not the engine, is what triggers the battery to drain. That's what I did on Wednesday and Thursday, the first days it needed a jump. I would just chill in the car and run the electronics, so I could listen to music through the car speakers from my phone. Friday I didn't do just electronics, I turned the whole thing on and didn't have any problems.

None-the-less, I replaced both terminals and got those nice and tight on the battery, so for whatever that would do, it's done lol.

 

Go to your local parts store. Usually they'll do a charging test for free.

My G35 did that and it was just a bad battery that didn't hold a charge.

 

Hello friends! Sorry for disappearing, life got away from me.

Where we're at now: Car has had zero problems turning on and staying on. That might be because I don't run just the electronics during my breaks at work anymore. If I'm at my car during a break, I just leave it off or turn on the engine all together.

In the meantime, I did replace the leads with some that were much more tight on the battery. The effectiveness of this remains to be seen though, because I have not run the electronics by themselves since replacing the leads.

This question is unresolved: Why would only running the electronics on the vehicle end up draining the battery in less than a day's time? I can still leave the vehicle untouched over a full weekend and have no problems on Monday morning.