Alternator at 15v
#1
Alternator at 15v
I was washing the car and went to start it and thought it slow cranked it seemed. then went to restart after drying and it wouldnt. (lights and radio were on while drying) maybe 10 mins.
came back and it barely started and worked fine. checked voltage and its 15 volts.
i know alternators fail 2 ways. 1. Completely dead 2. Overvolting
either bad battery or 15 volts is too much.
opinions?
oh and i got home shut off for few mins and came back it started right up
came back and it barely started and worked fine. checked voltage and its 15 volts.
i know alternators fail 2 ways. 1. Completely dead 2. Overvolting
either bad battery or 15 volts is too much.
opinions?
oh and i got home shut off for few mins and came back it started right up
#5
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id bet its your battery. if the car is hard to start you likely have a cell going bad, it will suck a lot of current trying to keep it charged to the alternator has to overwork and itll often see higher than normal voltage.
try this: start the car and while its running unhook the negative battery cable, then check the voltage between the voltage. if it goes back to normal, you know whats causing the issue.
try this: start the car and while its running unhook the negative battery cable, then check the voltage between the voltage. if it goes back to normal, you know whats causing the issue.
#7
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what ended up being the issue? i'm having the same problem but i replaced my battery at the beginning of this year, so i was leaning more towards the alternator.i have a system in my car and have noticed the lights flicker while i'm stopped and while i'm driving as well.
#9
ok...heres the rule of thum on batteries....you should have the car where it WILL NOT start but crank ONLY....take a digital multimeter and hook up the leads on the battery....crank for 15 sec and if the voltage drops BELOW 10.6 volts then the battery is bad....DONT DISCONNECT the battery while the car is running...you could have a surge and screw up the ECU.....also....how old is the battery....any extra loads on the car....Ive had the stock stereo going while it was charging my iphone...and I killed my battery....but that was on for like 3 hrs...if your alternator was @ 15V....its ok...its a lil high...but normal alternators run around 14.2-14.6 volts...depending whats needed while its running and the charge state of the battery or how hot or cold it is....also....where did you get the 15 volts from...if you used a DMM..what brand....some brands are no that accurate...
#11
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Nhanson or mrgrinch,
I understand that a trip to the dealership may not be your plan of attack on the situations you're describing with your vehicles. If, however, you do decide to work with a dealership towards a diagnosis, I'm happy to be of assistance.
Enjoy the last few bits of 2011!
Sarah
GM Customer Service
I understand that a trip to the dealership may not be your plan of attack on the situations you're describing with your vehicles. If, however, you do decide to work with a dealership towards a diagnosis, I'm happy to be of assistance.
Enjoy the last few bits of 2011!
Sarah
GM Customer Service
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