Installed Alt, Problems with Lights????

[donpisto 5,000+ posts]

I replaced the stock alternator with a 160A alternator so it will help with all the additional electrical equipment I'm running (sound system). Since the install (it was a direct bolt on and used the OEM casing, just has a smaller pulley and more amperage) I have a problem where every now and then, mostly when I'm braking and the speedometer shows below 10 mph or so, the lights for the low battery, emergency brake, and doors and trunk being open light up.

This doesn't happen all the time, but it does happen often. Sometimes it will flash rapidly. When the vehicle is stopped and I put it in neutral and back to drive, it stops and goes away the moment it is in neutral. I have checked my battery and its sitting at 14.5V while running and 12.8 while rested for a while.

I was told by the person who sold it to me that the computer needs to be reset. I go to the dealership and the guy says he doesn't think that will do anything but can do it if I want, but it will cost $90 (labor charge per hour even though it will only take like 10 mins). And he said if that doesn't fix the probelem, then who knows what will, they would have to inspect and that would cost an additional $90 per hour. I'm not lookin to do that so I'm seeing what other options I have or if anyone knows how I can reset the computer myself. If it's not too difficult, maybe I can try it out, or if anyone knows what else this might be that would be great. Thanks!

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[lilmaniac2 5,000+ posts]

to reset the computer you should be able to unhook the battery and try and turn the car on, but thats just me.

also the problem is probably related to the idle output of the alt. what rpm does your car idle at? what is idle output supposed to be

where did you get the alt from

 

[bryce-man 10+ year member]

to reset my truck i unhook the battery for 15 minutes and let it idle for about 5

id if thatll help you out but .. why not give it a try.. 5 minutes of gas is alot less that 90 bucks haha

 

[innsanes 10+ year member]

yah just unhook the battery for like 15 miin and let it idle for 5 min.

 

[IgnoreMe 5,000+ posts]

I replaced the stock alternator with a 160A alternator so it will help with all the additional electrical equipment I'm running (sound system). Since the install (it was a direct bolt on and used the OEM casing, just has a smaller pulley and more amperage) I have a problem where every now and then, mostly when I'm braking and the speedometer shows below 10 mph or so, the lights for the low battery, emergency brake, and doors and trunk being open light up.
This doesn't happen all the time, but it does happen often. Sometimes it will flash rapidly. When the vehicle is stopped and I put it in neutral and back to drive, it stops and goes away the moment it is in neutral. I have checked my battery and its sitting at 14.5V while running and 12.8 while rested for a while.

I was told by the person who sold it to me that the computer needs to be reset. I go to the dealership and the guy says he doesn't think that will do anything but can do it if I want, but it will cost $90 (labor charge per hour even though it will only take like 10 mins). And he said if that doesn't fix the probelem, then who knows what will, they would have to inspect and that would cost an additional $90 per hour. I'm not lookin to do that so I'm seeing what other options I have or if anyone knows how I can reset the computer myself. If it's not too difficult, maybe I can try it out, or if anyone knows what else this might be that would be great. Thanks!

listen to the guy at the dealer. resetting the computer wont help.

first read this thread and tell me if it sounds familiar.

http://www.caraudio.com/forum/showthread.php?t=265433&highlight=alternator

second, what brand alt is it?

the problem with a lot of HO alts is the fact that the cut on rpm is just way too high. for example, my buddies motor city reman alt wouldnt charge in neutral or drive (after the car warmed up and the idle came down). we ended up picking up the smallest pulley motor city reman had. installed it on the alt, put the alt back in. car charged fine in nuetral, but as soon as a load was put on it (by putting it into drive) and the rpm's came down...same situation.

at the least, your going to need a smaller pulley, which might or might not help. you can also ask the guy at the dealership to raise the idle speed.

 

[donpisto 5,000+ posts]

Idle is at about 750 rpm, which is what the stock alt was at. Sometimes it drops a tad below that but goes back up. The odd thing is, sometimes it does it, sometimes it doesn't and USUALLY when I'm braking and in first gear (automatic ******). Though, I have realized that it has done it a couple times when I have been in a higher gear and a higher RPM, but it was maybe 3 or 4 times total in that situation. I will try unhooking the battery for 15-30 mins and letting it idle for about 5-10 mins, hopefully that will solve things.

George, my problem doesn't seem to be anything like oomeskoo's situation. I actually swapped subs and in the process noticed the gain was set at 3/4. I set it back down to 1/2 and its fine. Get some dimming, but not too bad.

As for the alt, I got it from http://www.qualitypowerauto.com. They used to be about 10 mins from me, but changed their location and are a lil over an hour away now. Dalucifer and dragnix both have bought alternator's from him. However, he primarily deals with GM and Ford's. Originally he got me a GM alt but the casing was too big and wouldnt fit so he made some calls and got me an alt with 10A less that had the OEM casing. I posted on a Honda Forum, but not much luck there. Worst comes to worst, I'll call the guy up and see what goes on from there, but if it can be solved beforehand, it would be much better. I really don't like having to go every other week and waste 3 hrs of my day when I got other errands to run.

 

[IgnoreMe 5,000+ posts]

Idle is at about 750 rpm, which is what the stock alt was at. Sometimes it drops a tad below that but goes back up. The odd thing is, sometimes it does it, sometimes it doesn't and USUALLY when I'm braking and in first gear (automatic ******). Though, I have realized that it has done it a couple times when I have been in a higher gear and a higher RPM, but it was maybe 3 or 4 times total in that situation. I will try unhooking the battery for 15-30 mins and letting it idle for about 5-10 mins, hopefully that will solve things.
George, my problem doesn't seem to be anything like oomeskoo's situation. I actually swapped subs and in the process noticed the gain was set at 3/4. I set it back down to 1/2 and its fine. Get some dimming, but not too bad.

As for the alt, I got it from http://www.qualitypowerauto.com. They used to be about 10 mins from me, but changed their location and are a lil over an hour away now. Dalucifer and dragnix both have bought alternator's from him. However, he primarily deals with GM and Ford's. Originally he got me a GM alt but the casing was too big and wouldnt fit so he made some calls and got me an alt with 10A less that had the OEM casing. I posted on a Honda Forum, but not much luck there. Worst comes to worst, I'll call the guy up and see what goes on from there, but if it can be solved beforehand, it would be much better. I really don't like having to go every other week and waste 3 hrs of my day when I got other errands to run.

yea i noticed just now in this post that it doesnt match up with what is usually ( i would say) about 90% of peoples problems with HO alts.

try contacting jdawg on this forum. he knows a lot about the gm vehicles. it is my best educated guess that resetting the computer will not work to change anything. however, considering i havent worked on hardly any gm's, and dont know them inside and out, i cant tell you for sure.

jdawg would be your best bet as to what might be the issue.

 

[donpisto 5,000+ posts]

Well the original alt I was going to use was from a GM, but the one I'm using, the guy got it from someone who only deals with import alts. So this isn't a GM alt like the first one. I'm thinking that maybe something is vibrating and a wire is touching something and it may be causing that. The thing is, I don't know what it could be since it was a direct bolt on and no other wires (other than the ones that connect to the alt) were touched. I'd put in the stock alt, but it's a PITA to get the current one out and even more to get it back in. It's easy access since it's on the top but theres a bunch of crap in the way that makes it difficult. Plus, I don't want the stupid bolt to break in half on me again //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif