While driving my 2008 3.5 my Battery & Brake lights will flicker simultaniously then stay on, then all the other dash lights (except SES) turn on and the car is in limp mode. Then after rolling a bit it will go away. I replaced the Battery, Alternator, Brake Switch and Positive battery terminal and its done nothing. My Negative terminal has some corrosion but at this point i'm not sure if that could be the reason. And help or tips would be appreciated.

Hey Salvy, I think your alternator may be going bad. At least, that's what your lights mean. It's new, so perhaps it's a defective unit or installed incorrectly. If I did it, I'd double check all the wire connections and grounds related to those new parts. Can you get to a local parts store anytime soon? Many have free battery and alternator testing. I think you need that test. Let us know how you decide to proceed. Thanks.

centralcoaster33 wrote:Hey Salvy, I think your alternator may be going bad. At least, that's what your lights mean. It's new, so perhaps it's a defective unit or installed incorrectly. If I did it, I'd double check all the wire connections and grounds related to those new parts. Can you get to a local parts store anytime soon? Many have free battery and alternator testing. I think you need that test. Let us know how you decide to proceed. Thanks.

So I took it to my local Autozone and the battery and Alternator passed the tests. I also managed to get it into limp mode (I found that when i first start the car and rev it past 5k usually it triggers when the RPMs drop back down) and we scanned the OBD2 while it was in limp mode AND THE SCANNER SHOWED NOTHING. I don't know what else it could be!

Okay, did you do or have someone do some work recently? In addition to the above mentioned parts? I wonder if a sensor is unplugged or something, but I think you'd get a code from the scanner. It's time to refer to the FSM. What 'limp mode' do you experience? Fuel cut? Max RPM maybe?
Or you mean like no power, it's not running on all cylinders type stuff? Here's a link to the chapters to your FSM. FWD is the table of contents chapter. I recommend flipping through the EC chapter. There's a lot in there, so get a cup of coffee first.

http://www.nicoclub.com/FSM/Altima/2008/

centralcoaster33 wrote:Okay, did you do or have someone do some work recently? In addition to the above mentioned parts? I wonder if a sensor is unplugged or something, but I think you'd get a code from the scanner. It's time to refer to the FSM. What 'limp mode' do you experience? Fuel cut? Max RPM maybe?
Or you mean like no power, it's not running on all cylinders type stuff? Here's a link to the chapters to your FSM. FWD is the table of contents chapter. I recommend flipping through the EC chapter. There's a lot in there, so get a cup of coffee first.

http://www.nicoclub.com/FSM/Altima/2008/

Here is the car limping on the freeway: https://youtu.be/FLLOcHjRnnY
The only other work I've had done recently is I had subwoofers installed (by a shop) in January. As for the limp mode it will not rev past 1200RPM and I'm moving at idle roll speed. The battery & brake light flicker right before limp mode is engaged. In the video you see it engage, then I start to decelerate, then it goes away and the car drives normally. Also notice the speedometer drops to 0 while its limping. I don't know if its related but My stereo will randomly turn off and restart while this happens, not like a normal shutdown, but like it resets my clock.

I'll have to wait for a break to watch the video (I'm workin' today). For the sake of diagnoses. Temporarily pull the big fuse out of your power to stereo stuff or just disconnect it from your battery. Also, remove the ground to chassis wires you may have added for amps and stuff. Also, turn off your stereo head unit completely. Now test drive and see if you still get limp mode.

centralcoaster33 wrote:I'll have to wait for a break to watch the video (I'm workin' today). For the sake of diagnoses. Temporarily pull the big fuse out of your power to stereo stuff or just disconnect it from your battery. Also, remove the ground to chassis wires you may have added for amps and stuff. Also, turn off your stereo head unit completely. Now test drive and see if you still get limp mode.

I actually thought of that too. Last 3 days I've been driving with the power for the amp disconnected from my battery and I've driven with the stereo turned off and it still limps. I caved and took it to Nissan to be checked (even though another dealership originally diagnosed it as a bad alternator and battery terminal.) I will update when they call with what they find.

Ok so here's an update, let me know if you think it makes sense. When my regular mechanic replaced the alternator he must have put one in for a 2.5(110 amps) and the 3.5 requires 130. The Nissan technician said that why it would engage limp mode when I idled and sometimes when I revved since i wasn't getting the proper voltage. Does that sound like a plausible answer? Now I don't know what I'm going to do about my mechanic since he probably made an honest mistake but at the same time I paid for a new alternator from him and now I'm also $300 out of pocket for the Inspection from Nissan.

Oh damn. That's not good. What Nissan said is accurate, except for the "must have" part. Either he did or didn't install the correct alternator. There should be no guessing. It either is for the 2.5 or it's for the 3.5. He probably bought the cheapest one he could find. Your mechanic should install the correct alternator on his dime. I would inform him of the additional diagnoses and (damn $300 is expensive for a diagnoses) give him a chance to make it right. Did you have the same mechanic try to diagnose his own work and then have to go to Nissan? Hopefully you are dealing with a shop and not a random guy from craigslist.

My whole family works with him. He's a good mechanic but at times I don't think he is particularly knowledgeable about certain things (like my altima needing a different alternator) hence the reason I took it to Nissan to be inspected (and yes, they said an electrical system inspection is $275.) At first he attributed the bad alternator to my 1100W sound system but the Nissan Technician says otherwise. I will bring it back to him today to be checked out and give you an update when I have a new alternator.

I'm having the same problem, did the new alternator fix the problem?