Hi All,

Wondering if I can get some input from the forum on my latest issue.
All was well a few days ago and then I regrounded my amp/stereo directly to
the negative battery terminal in hopes that the stereo system would be better grounded to stop the alternator whine that I've been getting.

Anyway, since the re-routing, I've been receiving an intermittent simultaneous flashing of the battery and brake light on the dash. I know that this usually means bad altrnator, but I just changed my alternator in December of '09 (95 Amp Napa brand due to limited availability from parts suppliers).

Yesterday, after driving about 30 miles, I made a stop off at pep boys, came back out and I couldn't start the car. The battery registered 12.6 Volts so I know it's OK. I disconnected and reconnected the negative battery cable and the car started, but drove like crap (sluggish, course, loud, acceleration
was not responsive like normal) all of the way home.

Today the car started normally, but about 5 miles into my commute, I started getting the intermittent battery and brake light again. The lights flashed for a few seconds, but then went away. The car ran normally, not sluggish like last night.

Anyone have a clue what could be causing the intermittent flashing? Is it definitely the alternator again? Could all of this be caused by the regrounding of the stereo? Could it be anything else? A bad alternator shouldn't cause sluggish performance, should it?

I am completely at a loss for what's going on?

Any help would be greatly appreciated...

 

That's what nissans do to tell you the alternator is failing. I have not heard of it being anything else.

 

A blown engine cont fuse will display the brake and battery lights, run like crap, and cause the car to not start on the next startup attempt. My O2 sensor wires were shorting out and causing the eng cont fuse to blow on a VE of mine years ago. Took me forever to figure out the problem

Yours doesn't sound like the eng cont fuse because you were able to restart it. However, sounds like your wiring is causing the issues, especially if the car had none previously. If it were me, I'd remove that wiring/strereo, verify the car is fine, then re-do the wiring/stereo. It's also not out of the question that your new alternator is already bad, especially if the alternator was a rebuilt one

Why did you ground directly to the negative battery terminal? You want the ground wire as short as possible and ideally the same gauge as your power wire

 

the alternator is going out...for sure

 

That compounded with a flaky connection at the negative battery terminal.
Thanks to the re-grounding scenario.

 

yep, failing alty. had the same thing last year, ABS light was on, wipers and radio turned themselves on, weird noises, parked for 2 hours and it wouldnt start

 

your wipers/radio would not turn on randomly by themselves.. your car is possessed, man...

 

thats what happened when my alty went, the wipers would randomly quit or speed up themselves and my radio would turn on, and the heater would turn itself on and off

 

Alright, over the weekend I rewired my entire stereo system and regrounded to the trunk. I also added in a capacitor, ground loop filters, and noise chokes. The system sounds great and I am having no issues with the stereo. I also left the ground wire back to the negative battery terminal.
I got no warning lights all weekend.

This morning, while driving into work, the battery and brake lights flashed again and stayed on for a little while, then went off. While they were on, I looked in the trunk at the digital capacitor, and the voltage varied between 13.8v and 15.8v?

Can an Alternator put out more than the standard 14 or so volts with the engine running? Is there any danger if the alternator is putting out more?

I know that the battery and brake lights flash if the voltage in the system is too low, but could they be flashing if it's too high?
What would cause the voltage in my system to be too high?

Any suggestions? I don't just want to throw alternators at the car since they are around $200 a pop. Especially if the problem is somewhere else.
Is there anything else to the charging system that would cause this variance from the norm?

Please help...

 

I say it again......replace the alternator.......

 

agreed. battling issues in my brother's 77 gmc putting out similar voltages, fried two radios (thankfully, they cost pretty much nothing). but it's not got an ecu to worry about, so it's low priority.

on a car with a computer, and as much work as you have done to the stereo system, fix it, now.

 

^^^This


Mine did what you are talking about. The alternator was overcharging the battery. It will eventually shoot out battery acid in the engine bay from overcharging.

 

Simple test is to start the car, then disconnect the negative terminal on battery. If the car stops running, then the alternator is bad. Or you can take it to a parts store to test it. Get a lifetime warranty on it. Mine was free to replace...with another reman'd alty.

Speaking of problems, I just replaced my fuel pump AND alternator (replaced by me in 9/2008) while driving this past holiday weekend. Totally uncool when you're on a roadtrip.

 

If it is intermittent, that test can not be conclusive.
I had a very intermittent alternator issue on VE1. It tested good, but the 2 lights on the dash would flash sometime. I finally had my mechanic drive it and the lights came on we went back to the shop and replaced the alternator right then. Problem was gone.

 

Just thought I would say thanks to everyone for their suggestions and let you know how it ended.

The max had two separate issues which I addressed on Saturday.

My intermittent flashing of the brake and battery light turned out to be caused by the alternator. Once I removed the alternator, I noticed that the terminal where the positive/power cable screws on was totally broken. The screw post was also bent, and the plastic screw terminal was jiggling around and that's what was causing the warning lights to flash intermittently. Not sure how any of this happened, but I replaced the alternator with a new unit from Starters-Alternators on ebay. Only $85.00 plus $20.00 shipping. I'll lt you guys know how it holds up.

My intermittent no-start issues were caused by a bad Starter solenoid. I decided to stop tapping on the solenoid, and just replace with a new unit from Discount Body Parts off ebay. I only paid $79 and got free shipping. I'll let you know how this one holds up as well.

Thanks again for everyone's help!