Bad alternator?

r18-power

r18-power

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so I dont know what is going on, my car's radio restarts and the car's dash light dim just a little when I put my car in reserve it's happening usually when I drive for more than 30 mins, then when I go home and put the car in reverse to park it it happens, it happened again today I took the car out of reverse and put it back and it happened again (radio restarts as well) and when I went to put my windows up the dash light dim (more than usual when I put the windows up) and the car feels like it wants to turn off... After I shut the car off and start it up again the car is just fine like nothing happened I put it in reverse and its just fine.. I popped my hood and took a pic of my alternator and it looks (burnt)? On the coils? Or is that how is supposed to be?


 
I have a kicker 600w amp and kicker 12" sub and Im afraid it may have damaged the alternator?
 
A part's store like advanced should be able to test the alternator (I assume). At my job the battery tester's we use have a starter and alternator test function as well as the battery test.

As far as the radio reset going into reverse... is the radio stock or aftermarket? If you've spliced wires, there is a possibility of an issue there or wires rubbing/chafing if components were not placed back correctly. Does your lights dim on heavy bass while listening to music? I would assume something might have been damaged if your drawing that much amps. The discoloring isn't a guarantee that something is fried, if it smells like burnt electronics then yes I would say there is a problem. Another easy way to see the output of the alternator is put a volt meter on the positive and negative terminals of the battery while its running. You can load it down by your system plus the blower motor on high as that draws high amps as well as your high beams on and see if the voltage drops. Anything over 13v I would say is ok but 12.9v or less would start making me think problem.
 
Yeah im going to try autozone tomorrow, and its the stock unit on my 15 Si, im not sure about the lights dimming with loud bass I will have to check on that tomorrow, ok It looks black so I thought it was burnt or something and yeah I dont know its stupid weird how its only happening in reverse, oh another thing I had these LED projector reverse bulbs, I swapped them back to stock today after all this happened maybe thinking its the led bulbs making that happen since its everytime in reverse? So Ill see how the stock ones do tomorrow
 
I wouldn't think it's the alternator with just 600w... Maybe something with those reverse lights... U have to remove the alternator to get it tested. I would take the reverse lights out and try that first. I have been running 500w + for nearly 16 months and have not had any issues


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Another test - disconnect the power to the amp and see if you get the same thing happening.
 
You don't have to remove the alternator to test it. The machines should ask to to have the car idling with no loads and with higher loads (high beams/blower on high) as well as revving it up to 3k or so to see if the alternator responds to rpm and increased loads.
 
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13blacksedan said:
I wouldn't think it's the alternator with just 600w... Maybe something with those reverse lights... U have to remove the alternator to get it tested. I would take the reverse lights out and try that first. I have been running 500w + for nearly 16 months and have not had any issues


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Yes I wouldnt think so and I did remove the lights and drove 35 mins to work in the morning and put the car in reverse and everything was just fine! Im thinking it was maybe the led bulbs making a bad connection or something.. Drove the car back from work for another 30-35 mins and put in reverse and again everything was fine!

webby said:
Another test - disconnect the power to the amp and see if you get the same thing happening.
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Thanks webby I will try this if it happens again, hopefully everything is good now and for good!


Darkout said:
You don't have to remove the alternator to test it. The machines should ask to to have the car idling with no loads and with higher loads (high beams/blower on high) as well as revving it up to 3k or so to see if the alternator responds to rpm and increased loads.
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Well on my work back from work today I stop at an advanced auto parts, the guy went to test my battery/alternator and wasnt able to do it because the machine he used wouldnt read the battery and the guy was complaining alot about my bat location (I have a prl cai with bat relocation) so I was like screw it I told him thank you and goodbye, I went to Walmart and bought myself a multimeter and followed the multimeter test to see if the voltage would drop/go up or something and Everything checked out just fine, I also tested my wifes Mazda CX5 and the reading was alot lower than the recommended lol so I was supprised with that im not sure how accurate the multimeter is but everything checked out from the test I did... Here are the results M is Mazda H is honda..

 
Yea your alternator is fine. The mazda didn't need more than 13.2 to run everything so why push the alternator harder is the logic programmed in the car. The logic in the Honda is different and might have more loads to operate if you had your system on. I say everything checks out.

I dunno exactly what advanced uses but sounds like the guy just didn't wanna do anything.
 
@Darkout Thanks for all the info man!

Well today was not so good.. I was doing a datalog for vit everything went fine I did my 3rd gear pull drove about 4 miles, I hit vtec in second gear and shifted into 3rd then decided to put the car in neutral (was going about 45 mph) when suddenly my car shut off and restarted it self (As the car was rolling) I freaked out a lil cause I lost all power of the car for about 2 secs.. Then all the lights on the dash came on, the radio reset itself and then the car turned back on.. Anyway went home to park the car (another 2 miles or so) and put the car in reverse and the same problem I was having before happened, the radio reset and the car felt like it was loosing power, the dash lights dimmed.. I really dont know what to think anymore.. Im going to take out my amp and sub and see of that helps like @webby said.

Anyone have an idea what could be going on? From the test I did yesterday with the multimeter everything checked out just fine?
 
Just disconnect the positive wire on the amp. I can't really see that causing your issues, but I really have no clue.
 
If your going to disconnect the positive wire on the amp, make sure you tape it up or take your fuse out. If that wire touches anything metal connected to the chassis you could cause a short/blown fuse/fire possibly. I would go with ground wire over positive. Disconnecting the amp to eliminate it is a great idea.

The problem sounds like a wire issue to me considering the random symptoms and can't say I have heard anyone else with similar a issue during a vit tuning or using a FP.

Seeing as reverse is the culprit for the lights dimming and what not, have you looked to see if a cable is rubbing somewhere funny in the center console? If you don't have wires running by the shifter then ignore that. You had original reverse light bulbs in when this happened? I know you where swapping back and forth. I'd be curious what a volt meter would read when this happens.]

Last thing is that I have had issues with a system/amp when I owned a jeep and tried rigging the inputs for the amp to a factory head unit and factory amp setup. I would have to turn the radio on a certain way or multiple times in order for the aftermarket amp to turn on as well as getting nasty speaker pop when turning the the head unit on and off.
 
r18-power said:
@Darkout Thanks for all the info man!

Well today was not so good.. I was doing a datalog for vit everything went fine I did my 3rd gear pull drove about 4 miles, I hit vtec in second gear and shifted into 3rd then decided to put the car in neutral (was going about 45 mph) when suddenly my car shut off and restarted it self (As the car was rolling) I freaked out a lil cause I lost all power of the car for about 2 secs.. Then all the lights on the dash came on, the radio reset itself and then the car turned back on.. Anyway went home to park the car (another 2 miles or so) and put the car in reverse and the same problem I was having before happened, the radio reset and the car felt like it was loosing power, the dash lights dimmed.. I really dont know what to think anymore.. Im going to take out my amp and sub and see of that helps like @webby said.

Anyone have an idea what could be going on? From the test I did yesterday with the multimeter everything checked out just fine?
Click to expand...

If by the "car shut off and restarted it self" you mean it "skipped a beat" then you're looking for a cable short/intermittent likely rubbing on your shifter or linkage. If literally the starter engaged to re-crank it - GOKs!
Retrace/remove any wiring you've modified as that's the likely (99%) source - There's a very small possibility you've got a bad main circuit breaker or loose battery cable (dash dimming with windows opening).
 
webby said:
Just disconnect the positive wire on the amp. I can't really see that causing your issues, but I really have no clue.
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Yeah I just took out the amp for now.

Darkout said:
If your going to disconnect the positive wire on the amp, make sure you tape it up or take your fuse out. If that wire touches anything metal connected to the chassis you could cause a short/blown fuse/fire possibly. I would go with ground wire over positive. Disconnecting the amp to eliminate it is a great idea.

The problem sounds like a wire issue to me considering the random symptoms and can't say I have heard anyone else with similar a issue during a vit tuning or using a FP.

Seeing as reverse is the culprit for the lights dimming and what not, have you looked to see if a cable is rubbing somewhere funny in the center console? If you don't have wires running by the shifter then ignore that. You had original reverse light bulbs in when this happened? I know you where swapping back and forth. I'd be curious what a volt meter would read when this happens.]

Last thing is that I have had issues with a system/amp when I owned a jeep and tried rigging the inputs for the amp to a factory head unit and factory amp setup. I would have to turn the radio on a certain way or multiple times in order for the aftermarket amp to turn on as well as getting nasty speaker pop when turning the the head unit on and off.
Click to expand...

Yeah so I took the amp out and went for a ride yesterday and again everything was fine, I was nervous to get on the car hard because I didn't know if it was going to turn off again or not.. Im going to keep the multimeter in the car just incase it happens again Ill check what it reads, I really hope it doesnt happen again, I had a queetion though lets say it was the alternator could that really make the car shut off for a few seconds while being rev'd high? Due to all the load the car is under in high rpms? I pretty much took all the amp wiring out of the car for now.

Nix said:
I have no idea. I've read through a couple times but I don't know.
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No problem, Thanks for the reply Nix

tacthecat said:
If by the "car shut off and restarted it self" you mean it "skipped a beat" then you're looking for a cable short/intermittent likely rubbing on your shifter or linkage. If literally the starter engaged to re-crank it - GOKs!
Retrace/remove any wiring you've modified as that's the likely (99%) source - There's a very small possibility you've got a bad main circuit breaker or loose battery cable (dash dimming with windows opening).
Click to expand...

Yeah I would say thats what heppened, I didnt have any cables by the shifter or anything, I took everything out, I was thinking of taking it to Honda to see if they can check it out but they're probably going to blame it on my aftermarket parts.
 
If the alternator is bad then the car runs off just the battery and will eventually die but at that point the car wont respond or restart due to the dead battery, pretty basic. The battery is basically there to absorb any spikes the alternator puts out so you don't fry any ecu's and to give everything a steady voltage. Do you think that the starter is engaging when it restarts or are you positive it is? If your rolling in neutral when it shuts off then your probably just "push starting" it when you engage a gear. Have you made sure all your battery terminals and main connections are tight? A loose wire can cause some funky things.

I'm honestly like Nix and a little clueless as to what might be going on without physically seeing it happen. Try getting a video if it happens again
 
Yeah thats the funny thing though, the car never struggles to turn on or anything, I think so like I said the car pretty much turned back on on its own while it was rolling, I checked every wire yesterday and it seemed fine, you know something I forgot to tell you guys, When I had my amp connect I would get home from driving 30 mins or so and pop the hood to see how things looked and it would smell kinda like burned plastic/cables by the alternator and now that I took the amp out I drove today as usual and got home and smelled the alternator and it was just fine and I hit vtec 3 times today on my way back.. So maybe that was putting too much stress on the alternator? Who knows I dont want to call victory just yet, hopefully is fixed for good.. I was also told by someone that my car might have restarted because it could have went into limp mode while I did the second gear pull, which makes a lil since since that was a brand new calibration from vit..
 
So if you disconnect the amp for a few days and have no issues then you know its the amp. Maybe its drawing more than you think and the system can't keep up. Might need a capacitor? I know nothing of car audio but the basics from a brief stint working at BB.
 
Might be overloaded or possibly having some feed back that the car doesn't like. I'm no expert on car audio but have fried my fare share of amps and speakers to know that it takes some proper sizing up to get it all to run smooth. So far though it does seem to be linked with the amp.
 
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