i was out riding around the other day and my battery light would come on for a minute or two and then go off for a few minutes. it did this the entire 500 mile trip. it has a brand new alternator on it and its charging at around 14. one of the batteries was boiling over a little bit, so i went ahead and replaced both batteries. no sooner than i get out of my driveway does the battery light start coming on again. im going to take it by advance tomorrow and have them run a check on the alternator, because they have been known to sell me a bad part or two before.....anyone have any ideas on this one?

 

I have been having the flickering light also.......found that my hose for the heater core(the one that runs across the top of the alternator) was hitting the connections on the alt.(single wire plug to be exact)....a little bending with the loop the holds the hose,and a zip tie to keep the hose at the top of the loop......no more flickering bat light for me.

 

Last time I had an intermittant battery light it turned out to be the battery/cable connections. Dark grey film inside the lugs. Made them shiny again and 2000 miles later still no light.

 

I think is a bad regulator in the alternator.

 

ok, checked the heater hose and it was laying on the single wire. moved it around, made sure the wire was plugged in good, and the light kept coming on. ill clean the battery terminals tonight and see if that helps any. im thinking it may be the alternator too, but im going to try all the free options first lol. if the regulator in the alternator isnt working then it can overcharge the battery and cause it to boil over, which is what happened. i was hoping it was just a bad battery and i wouldnt have to buy both the battery and a new alternator, but its never that easy.

 

ok, next question. im looking at alternators online at advance. they have about 10 different types all the way from a 110 amp up to a 215 amp. normally i would just look at the alternator thats on the vehicle already, but too big of an alternator may be whats causing my problem to start with. the guy that had it before me had wires out the a$$ running from the batteries back to the cab and to the bed where it was a commercial truck. he only owned it for about 6 months and it has a brand new alternator on it, so im thinking that might be a possibility. too much amperage= overcharging=boiled over battery.

what would be the right size alternator for my truck? i have dual batteries, but dont run anything that requires auxillary power. just a stock truck for normal driving with some occasional towing.

 

I have this same problem. I had it before I blew my engine up and a month after I put the NEW engine back in the light started it all up again. All conections are good but I keep burning up napa alternators!! I got there biggest and best and the last two the coils turned black! The coils still look half way good right now but the damn light is doing its little strobe thing. I have come to ignore it but I probably should address it!

 

I had the same problem. It was the three wire plug coming off the alt. Take that connector off, pull the plastic red lock out and pull the pins out. Clean them, crimp them a little and reassemble. I bet you a dollar the problem will go away. For a test, start the truck at night, turn the running lights on and go out and wiggle that connector. I bet you will see the lights flicker. If so, that's your problem.