Bad Altinator?
Thread Starter
Race Director
Joined: Feb 2006
Posts: 10,336
Likes: 14
From: Bellville OH
St. Jude Donor '06
Bad Altinator?
Well based on http://forums.corvetteforum.com/show...post1563064258
and a new CHARGE SYSTEM FUALT message could it be a bad altinator that is draining the battery and now not charging it once the car is started?
How much does a new on cost and how hard is it to replace. To me it looks like it's two bolts and two connectors, take the tension of the belt??
and a new CHARGE SYSTEM FUALT message could it be a bad altinator that is draining the battery and now not charging it once the car is started?
How much does a new on cost and how hard is it to replace. To me it looks like it's two bolts and two connectors, take the tension of the belt??
Melting Slicks
Joined: Jul 2007
Posts: 2,939
Likes: 7
From: Simpsonville SC
St. Jude Donor '09-'10
My 99 vert gave me a CHARGE SYSTEM FAULT the other day. It came on for about 5 seconds, then went away. I put the DIC in the voltage display mode after that, and saw my voltage stayed around 14.0. I think mine was just a glitch. It happened right when the twilight mode turned off my headlights.
Thread Starter
Race Director
Joined: Feb 2006
Posts: 10,336
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From: Bellville OH
St. Jude Donor '06
My 99 vert gave me a CHARGE SYSTEM FAULT the other day. It came on for about 5 seconds, then went away. I put the DIC in the voltage display mode after that, and saw my voltage stayed around 14.0. I think mine was just a glitch. It happened right when the twilight mode turned off my headlights.
Le Mans Master
Joined: Jul 2005
Posts: 7,121
Likes: 3
From: Shreveport/Bossier Louisiana
St. Jude Donor '08
I priced them last week and they are over $200. Very easy to change though. On the passanger side you will see your tensioner, get a 15mm socket and push is towards the drives side and that will relive the tension off your belt. Then its just the 2 bolts and 2 connectors.
Former Vendor
Joined: Nov 2005
Posts: 8,995
Likes: 2
From: Spring Texas
St. Jude Donor '08
The swap is simple. You may need a beefy flathead for added leverage if it's been mounted a long time. Autozone carries an OEM replacement for ~$250. For reference, a GM part costs nearly double that.
Thread Starter
Race Director
Joined: Feb 2006
Posts: 10,336
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From: Bellville OH
St. Jude Donor '06
Checker had a refurbished one for 160 less 20 core charge once the swap is complete. Do I need to have the battery disconnected during this? Also I have it on a trickle charger now so it will be a full battery.
Former Vendor
Joined: Nov 2005
Posts: 8,995
Likes: 2
From: Spring Texas
St. Jude Donor '08
It can be done with the alternator connected if you're careful. if it's your first swap, I'd disconnect it .
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
Before replacing the alternator, always check the battery cables first. A loose cable will give you the same fault. A bad battery internally will also give that fault and lastly, the battery's positive post about to break off will cause the same fault message...ask me how I know!
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Thread Starter
Race Director
Joined: Feb 2006
Posts: 10,336
Likes: 14
From: Bellville OH
St. Jude Donor '06
Before replacing the alternator, always check the battery cables first. A loose cable will give you the same fault. A bad battery internally will also give that fault and lastly, the battery's positive post about to break off will cause the same fault message...ask me how I know!
It's a brand new battery and the cables where on tight (already checked during my first stage of trouble shooting) Ill wait till tommorow to remove the altinator.
Drifting
Joined: Mar 2003
Posts: 1,398
Likes: 1
From: Kingsport TN
Make sure you get only this alternator part # (see post #8 in this thread) otherwise you'll get a charge sys fault all the time like me! It's important to only use the GM part and avoid any other aftermarket ones because the pcm is very fussy about even slight variations:
http://forums.corvetteforum.com/show....php?t=1530169
http://forums.corvetteforum.com/show....php?t=1530169
Intermediate
Joined: Oct 2007
Posts: 29
Likes: 0
From: Grapevine Tx
Wire Problem!!! Check your Fuseable links!!!`
Hey there,
MAKE SURE you check the Wires that run from the alt. to the Starter then back up to the battery, On my 03 Z06 I was having the charger system fault and my volts would drop and sometimes jump back up.. but when the wires go bad ( norm, bc you changed to aftermarket headers and exhaust, pipes,) If you want to know how i fixed the wires i will email you pics, but what I did was cut the fuseable kinks out and reran straight wire around the back of the engine away from high heat and next to the battery I used a New inline fuse system used by Caddy and Navigators.. But wire goes ALT.-----------Starter---------FUSE BOX----Battery.
B4 i changed the wires I burned out 2 alternators bc when the line gets burned you put a strain on the alternator bc the battery is not helping run the car....
MAKE SURE you check the Wires that run from the alt. to the Starter then back up to the battery, On my 03 Z06 I was having the charger system fault and my volts would drop and sometimes jump back up.. but when the wires go bad ( norm, bc you changed to aftermarket headers and exhaust, pipes,) If you want to know how i fixed the wires i will email you pics, but what I did was cut the fuseable kinks out and reran straight wire around the back of the engine away from high heat and next to the battery I used a New inline fuse system used by Caddy and Navigators.. But wire goes ALT.-----------Starter---------FUSE BOX----Battery.
B4 i changed the wires I burned out 2 alternators bc when the line gets burned you put a strain on the alternator bc the battery is not helping run the car....
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
If I were you I would make sure that yours is really bad. I seen countless alternators replaced only to see the same issue and then upon further investigation, they figure out it was a bad connection on the starter, bad connector on the alternator or no voltage on the field wire.
Use a Volt meter (engine OFF) and check the LARGE red wire that is attached to the back of the alternator. You should read battery voltage. (what ever the battery is out putting). If you don't see battery voltage, thats probably the issue.
Once you start the engine, the PCM will tell the alternator to start out putting and you should see 13.5 -15.5 VDC on the same connection on the back.
I would keep the CORE until you determine that the alternator that they provide you is the correct one and doesn't cause a charging system fault.
I agree, disconnect the battery before you work on the alternator. The battery terminals must be torqued to 11 ft/lbs to be properly tightened.
BC
Use a Volt meter (engine OFF) and check the LARGE red wire that is attached to the back of the alternator. You should read battery voltage. (what ever the battery is out putting). If you don't see battery voltage, thats probably the issue.
Once you start the engine, the PCM will tell the alternator to start out putting and you should see 13.5 -15.5 VDC on the same connection on the back.
I would keep the CORE until you determine that the alternator that they provide you is the correct one and doesn't cause a charging system fault.
I agree, disconnect the battery before you work on the alternator. The battery terminals must be torqued to 11 ft/lbs to be properly tightened.
BC
Hey there,
MAKE SURE you check the Wires that run from the alt. to the Starter then back up to the battery, On my 03 Z06 I was having the charger system fault and my volts would drop and sometimes jump back up.. but when the wires go bad ( norm, bc you changed to aftermarket headers and exhaust, pipes,) If you want to know how i fixed the wires i will email you pics, but what I did was cut the fuseable kinks out and reran straight wire around the back of the engine away from high heat and next to the battery I used a New inline fuse system used by Caddy and Navigators.. But wire goes ALT.-----------Starter---------FUSE BOX----Battery.
B4 i changed the wires I burned out 2 alternators bc when the line gets burned you put a strain on the alternator bc the battery is not helping run the car....
MAKE SURE you check the Wires that run from the alt. to the Starter then back up to the battery, On my 03 Z06 I was having the charger system fault and my volts would drop and sometimes jump back up.. but when the wires go bad ( norm, bc you changed to aftermarket headers and exhaust, pipes,) If you want to know how i fixed the wires i will email you pics, but what I did was cut the fuseable kinks out and reran straight wire around the back of the engine away from high heat and next to the battery I used a New inline fuse system used by Caddy and Navigators.. But wire goes ALT.-----------Starter---------FUSE BOX----Battery.
B4 i changed the wires I burned out 2 alternators bc when the line gets burned you put a strain on the alternator bc the battery is not helping run the car....
Former Vendor
Joined: Nov 2005
Posts: 8,995
Likes: 2
From: Spring Texas
St. Jude Donor '08
If I were you I would make sure that yours is really bad. I seen countless alternators replaced only to see the same issue and then upon further investigation, they figure out it was a bad connection on the starter, bad connector on the alternator or no voltage on the field wire.
Use a Volt meter (engine OFF) and check the LARGE red wire that is attached to the back of the alternator. You should read battery voltage. (what ever the battery is out putting). If you don't see battery voltage, thats probably the issue.
Once you start the engine, the PCM will tell the alternator to start out putting and you should see 13.5 -15.5 VDC on the same connection on the back.
I would keep the CORE until you determine that the alternator that they provide you is the correct one and doesn't cause a charging system fault.
I agree, disconnect the battery before you work on the alternator. The battery terminals must be torqued to 11 ft/lbs to be properly tightened.
BC
Use a Volt meter (engine OFF) and check the LARGE red wire that is attached to the back of the alternator. You should read battery voltage. (what ever the battery is out putting). If you don't see battery voltage, thats probably the issue.
Once you start the engine, the PCM will tell the alternator to start out putting and you should see 13.5 -15.5 VDC on the same connection on the back.
I would keep the CORE until you determine that the alternator that they provide you is the correct one and doesn't cause a charging system fault.
I agree, disconnect the battery before you work on the alternator. The battery terminals must be torqued to 11 ft/lbs to be properly tightened.
BC
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
Ok, When I first got my '99, I got that message on the DIC. I got the car back home and went to check the battery cables and the positive cable fell off...yes, litterally fell off. It was immediately dumping acid. I ran into the house, grabbed a box of baking soda and doused the whole area around the battery with it. Then quickly found a plastic bucket and pulled the battery. I put more and more baking soda till I was sure the reactions had ceased then started the clean up. Putting a new battery in from Costco (the only place open at that time that had one), I never had that message again. Obviously in my case, it was the battery. I'm not saying its everyone's case and please follow Bill Curlee's posting as he's got good advice for sure.
Race Director
Joined: Jul 2004
Posts: 16,794
Likes: 62
From: Lake Havasu City, AZ
1. Bill Curlee is the electrical problem diagnosis guru for C5's... heed his advice well
2. Evil-Twin ( gone form the forum but not forgotten)
routinely posted of problems iwth aftermarket alternators. IF it is your alternator, find a local auto-electric shop and have them rebuild your currrent alternator. Many offer same day service.
It should cost $80 or less.
2. Evil-Twin ( gone form the forum but not forgotten)
routinely posted of problems iwth aftermarket alternators. IF it is your alternator, find a local auto-electric shop and have them rebuild your currrent alternator. Many offer same day service.
It should cost $80 or less.
Race Director
Joined: Sep 2003
Posts: 13,550
Likes: 6
From: Now in God's Country, the Big Sky, Montana!
Cruise-In 7-8-9-10 Veteran
St. Jude Donor '06-'07-'08-'09-'10-'11-'12
Individual internal parts are not available for the Valeo alternators, at least not that I have found and that is the case at a couple of alt shops that I asked when I needed a part. Any shop that would "rebuild" this alt would just be placing used parts in (assuming they have them) and simply cleaning up the stator and regulator, which shouldn't be a problem. I too hate the ridiculous pricing on GM parts but I can do a little something about it if you in fact do need a alt and want a new OEM one. The C5 alt lists for over $500 I believe but I do have a discount with GM and will sell one to you for $375 shipped which is around my cost to do so.
Jason
P.S. Definitely check the stuff over that Bill talked about as he knows his chit.
Jason
P.S. Definitely check the stuff over that Bill talked about as he knows his chit.
I will definitely ask the local auto electric shop where they get their parts.
Race Director
Joined: Sep 2003
Posts: 13,550
Likes: 6
From: Now in God's Country, the Big Sky, Montana!
Cruise-In 7-8-9-10 Veteran
St. Jude Donor '06-'07-'08-'09-'10-'11-'12
If you go to the dealer you will now get one alternator that will cover 97-04 and another for 05+. They all have the clutch pulley now and the casings are completely enclosed. They are no longer year specific. The new style alts are also a little more difficult to pull apart then the older styles due to the diodes that need to be pressed out and pressed back in upon reassembly. The regulator is a new design and the rotor and stator are also a little different in size so the majority of internal parts are not interchangeable. Obviously individual parts are availably somewhere but I haven't found them yet and neither has some people I have a good relationship with that own and alternator shop.
Le Mans Master
Joined: Jul 2005
Posts: 7,121
Likes: 3
From: Shreveport/Bossier Louisiana
St. Jude Donor '08
I just had mine rebuilt because I tried to take it apart to have the shell powdercoated, but I ended up messing up the 3 big wires that are soldered on. They only charged me $40 to rebuild it, but I dont imagine they had to do much.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Jason
Do you have a picture of this NEW Alternator???
I wonder if its better than the old Valeo types.
BC
Do you have a picture of this NEW Alternator???
I wonder if its better than the old Valeo types.BC
If you find something out, lemme know. I've checked into getting individual parts but have had no luck yet. I've even purchased new alts to get some of the parts before. If you go to the dealer you will now get one alternator that will cover 97-04 and another for 05+. They all have the clutch pulley now and the casings are completely enclosed. They are no longer year specific. The new style alts are also a little more difficult to pull apart then the older styles due to the diodes that need to be pressed out and pressed back in upon reassembly. The regulator is a new design and the rotor and stator are also a little different in size so the majority of internal parts are not interchangeable. Obviously individual parts are availably somewhere but I haven't found them yet and neither has some people I have a good relationship with that own and alternator shop.
If you go to the dealer you will now get one alternator that will cover 97-04 and another for 05+. They all have the clutch pulley now and the casings are completely enclosed. They are no longer year specific. The new style alts are also a little more difficult to pull apart then the older styles due to the diodes that need to be pressed out and pressed back in upon reassembly. The regulator is a new design and the rotor and stator are also a little different in size so the majority of internal parts are not interchangeable. Obviously individual parts are availably somewhere but I haven't found them yet and neither has some people I have a good relationship with that own and alternator shop.