Jimmy C-6

I have been getting the "Service Charging System" message just recently, but no problems with a dead battery. The message only come occasionally. What is the cause of this message? Is it time for a new Optima, or do I need to clean the battery terminals?
Thanks,
Jimmy

Corvee

It may be your alternator.

geewez

I've had that message come on twice before and both times it was a blown horn fuse.

dgrant3830

A couple of possibilities...bad battery cable connections at the battery. Bad battery to starter solenoid connections at the solenoid as it will get lose. Have you changed the spark plugs? Yes, spark plugs...?

Jimmy C-6

Yes I did have my tech change spark plugs and wires in September with NGK's and MSD wires from CC Performance parts, and I just wired in my battery tender for the winter, so,,,

http://forums.corvetteforum.com/c6-t...-anywhere.html

eboggs_jkvl

Fiddy cents says the NGK plugs are doing it. I recommend these: AC 41-104 gap them at .040


Elmer

dgrant3830

Go back to OEM plugs. I think the normal is 41-110's last I heard. NGK's will cause noise on the buss which is picked up on the horn/sense fuse and causes the PCM to improperly command the alternator.

Tally Ho

I agree with the NGK's. My car has been doing the same sporadically since the change. I plan to go to ZR1 plugs. My car is supercharged.

C7&7

Does it only happen with you start the car? What does the battery voltage read on the dash when this happens? Do you have a UDP or a cam?

My car does this after it has sit for a couple days and I start it. It takes the car a minute to charge the battery back up. Nothing to be alarmed about.

I have a hard time thinking it has anything to do with spark plugs.

eboggs_jkvl

fiddy cents is still out there for a wager! I think I saw that in a "Spinmonster" thread a while back. I pulled my NGKs and went with the ZR1 plug as I am supercharged.



http://forums.corvetteforum.com/c6-f...hlight=service



Elmer

dgrant3830

I too had the same misgivings about the plugs being the cause but another forum member SgtRod, had this happen to him as well. Between him and the dealer, they nailed it down. It was the plugs causing noise. Same on mine too. The alternators are commanded by the pcm on how much to charge or not. Its not the older alternators with a built in regulator as such...the pcm determines the need and sends the commands. It does this by measuring the spin frequency of the alternator and it does this, at the horn/sense fuse. If there's noise on the buss, which NGK's do cause, then the pcm thinks the alternator is turing faster or slower than it demands, so it issues charge changes as its programming deems needed. Trust me, I too thought, "no way can plugs have anything to do with the alternator". I was wrong.

Jimmy C-6

Well the car is going to sleep tonight so I guess new plugs in the spring.

eboggs_jkvl

Location: Michigan! You poor guy!



Elmer

Jimmy C-6

Tell me about it, 9 months of winter and 3 months of bad sledding, (

Gering

I have had this problem before when I am sitting at a red light with the A/C on. My problem was a loose battery terminal connection and a worn battery. After I replaced the battery, "Optima Red Top" the problem stopped. I also have an underdrive pulley.

Gering

OP: Check out these threads as well. http://forums.corvetteforum.com/c6-t...g-victory.html

http://forums.corvetteforum.com/c6-z...m-message.html

http://forums.corvetteforum.com/c6-t...esolution.html

http://forums.corvetteforum.com/c6-t...ng-system.html

TNTC4VETTE

Happening to me now as well. Had the alternator take a dump, replaced it, and still getting the message and the battery discharges. Volt meter in dash shows no charging, and just dies off as the battery goes. I charged the battery overnight to 100%, and it did it again this AM.

dgrant3830

The alternator has two fused paths down to the starter solenoid where the battery also comes to. This is the electrical interconnect or distribution point, so you might want to verify that the solenoid's main connection is tight. Do not forget that it's electrically hot unless you remove the battery's negative cable first.