hey guys,

how can i determin if my alternator is goiong or is bad? this is what im getting from the car. the last to days my car at start up has 14.2v as i drive the voltage goes from 14.2 to 13.8 to as low as 12.2. this morning i got in no codes on DIC the voltage said 14.2 all went well. any ideas.

FYI the voltage from the batery (before start up) is 12.0

the only code im getting is the c1214 code that is happening itermitenly. from what i can tell i get the code when the volts drop to low.

Could be the voltage regulator is starting to go. I've replaced a number of alternators on Corvettes and it's a pretty easy job. You could take the alternator to one of the autoparts stores and get it tested.

ill take it today do you know if its going bad will they also be able to determin that>?

I had this happen to me. I took it to the local Kragen store, they tested it and then sent it to a repair shop....two hours later it came back with " no cost". They found a lose wire connection. Unit has been fine still. Just a lose "nut". Later, JA

I dont think the alternator is bad what is the condition of the battery.. hot weather is hard on batts and how much are you drivin versus short trips. That code will set with low voltage and many rebuild the ecbm cause of it.

hello lead,

i really need your help now , this afternoon driving home first my radio goes off then all i get a check egine light one , service active handing , low fuel , shocks not something cant remember what that one said. along with that my windows would not go down., also had reduce power and max speed 80mph. i was able to make it to my house. i turned the car off and now it wont start at all it will not even crank. i have lights on my shift and my dash thats about it the car fob will not work and the light on the hood has no power. any ideas this is my daily driver about 50miles a day more or less mostly highway. where do i start.

I am going to go with a bad battery...next???

How sure are you about the battery radar do the systems match ?

You can never be 100% sure of electrical issues with a C5 due to the many ground issues they have. However, your symptoms match up with what happened when the battery went out in my 2001 a few years ago. Pull your battery and have it checked out at a Auto Zone or Pep Boys and go from there. Let us know what you find.

I think u have a grounds isuue here..... I had all those symptoms happen to me, but mine started on the second attempt to turn the key...... After cleaning the grounds ( My shop did that) I have no issues what so ever, I had a battery reading just like yours and all the messages were the same including the FOB-mine wouldnt open passenger door. Clean the grounds-its the cheapest way to try and solve the problem.
Good luck,

Martin I know yours sytems where just the same as mine , with the exception my car won't start back up , Im gonna pick up baterry when auto parts opens and I'll post what I find wish me luck

Martin I wanted to add that the grounds under the hood where cleaned by me not to long ago all was working fine.

Both batery and alternator tested ok , batery had an eggie smell to it and was 2 yrs old so I changed it for a red atum batery.

Sooooo...did the new battery help?

Nope , took it to my local guy he checked all the grounds and determain it looks to be the alternator were replacing it and going from there. I'll keep you guys concerned one thing is for sure it's not the batery or the ground points I even went as far as replacing g the metal post screws on the batery