[zaluba]

New alternator NAPA 213-9453 (they say equal to AMR2938) and new NAPA battery. Battery steadily discharges after three
days to around 9.5V. Voltage at battery when running is @ 14V. Battery charges when it reaches around 9.5 V up to 12.5V by the alternator.
Is this the correct alternator? Also. I am showing 12V at the red power lead to the alternator. Is this normal? Parasitic test
shows no unwanted draws to the system. Thanks in advance.

 

[NorCal RR]

Slightly contradictory there. How is the battery dropping to 9.5V without a parasitic loss? If this happens to a battery that is disconnected from the car, its defective. Did you see the electrical stickie?

 

[zaluba]

Thanks, Yes, I do not understand how the battery can drop voltage without a drain somewhere, but where? Can the alternator
drain the battery after the engine is shut down and the BECM goes to sleep? I do not know where this drain is coming from. Makes to
sense.

 

[chris no 10]

There’s lots of ways it can draw and drain, if you suspect the alternator, then disconnect the lead to it, stick a bit of hose over it to stop a short, you definitely need to go through the electrical sticky, are you sure the becm is not being woken up ?, ive had the same problem this year, my car is sleeping but being woken by a wireless signal now and then.

 

[Bolt]

New alternator NAPA 213-9453 (they say equal to AMR2938) and new NAPA battery. Battery steadily discharges after three
days to around 9.5V. Voltage at battery when running is @ 14V. Battery charges when it reaches around 9.5 V up to 12.5V by the alternator.
Is this the correct alternator? Also. I am showing 12V at the red power lead to the alternator. Is this normal? Parasitic test
shows no unwanted draws to the system. Thanks in advance.

You need to tell us just how you did your "parasitic test"? find a clamp on ammeter that will do DC and snoop around.........
B+ on the fat red lead is normal, and not a worry unless the diodes in the alternator are no good. Again, easy to determine with clamp meter.

My main question is about your claimed geographic location in Nice,France relative to the nearest Napa store:shock:.......
If we do not know which country you are in, we may give less than accurate answers to some questions......

 

[Reinhoud]

A battery can be bad, and look good..
Can be good for a couple of days, and then, one day when you try to start it, it won't crank the engine over...

New battery is the remedie than. Try another battery.

 

[zaluba]

Thanks. I am recently returned to Colorado and have updated my location. My shop did the parasitic test. They are trusted and found only one 7 amp hit for about 3 minute. Ran test for 24 hours.
I believe I have found the problem as the ground on the alternator was not properly fixed. Battery now seems to be charging normally while vehicle is in use. Thanks for your
help. Your knowledge of these problems is unmatched.

 

[DaGlitch]

A 7 amp draw for 3 minutes doesn't seem right to me. I would expect the current to be around .8 amps or something before the BeCM goes to sleep after a few minutes. I think something is still a miss.

 

[chris no 10]

if It didn’t happen at there garage, but does at your home, it sounds like the becm is getting woken up by a wireless device where you live, sounds like a rf receiver upgrade is needed

 

[Bolt]

Glad you found the issue. (that is the kind of thing the electrical sticky is written for.)

Was that a 7 amp draw or a .7 amp draw?
as stated, 7 amps is a worry, but .7 to .9 would be acceptable.
Thanks for changing location, that made my brain hurt!
Cheers,

 

[zaluba]

Thanks, the shop said it was seven amps but I suspect .7 is correct.