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Check Charging System Message

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ArizonaGT said:
Just got the call from the dealer--they are replacing the alternator. I might try to fashion a heat shield before Chuckwalla...
Good luck with that. They replaced mine but the message came back anyway. Were they in stock? They were on backorder when I got mine so had to wait a while.
 

ArizonaBOSS

Because racecar.
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At the local warehouse, part arrives tomorrow and I'll have the car back in the afternoon. I read backwards in the thread and saw you're still having the issues :(
 
ArizonaGT said:
Just got the call from the dealer--they are replacing the alternator. I might try to fashion a heat shield before Chuckwalla...
I think we found it! I should have snapped a pic but didn't think about it. My car's up on the lift right now to install the headers and we found a few quirky things. First a minor oil leak near the filter.....assuming the filter didn't get seated initially since there is no oil on the garage floor but will obviously check that and the lines going to the cooler. The second thing was wear on the sound deadening material from the wiring on the O2 sensors coming off the H-pipe.....apparently the exhaust is flexing the like a mofo! The most interesting thing was a wiring harness running up the inside of the passenger side fender well to the battery. The black plastic shield appeared to be melted in several spots (that or mice chewed throught it :D) I am guessing that's causing that error code. We're going to wrap it in header tape to protect it from the heat. You should inspect yours to see if it's in similar condition.
 
If this is the harness you are talking about it looks good on mine. Also it is wrapped up and spaced pretty far from the headers. Was yours wrapped like this? If you are having a problem further underneath I can't get in there without taking off the lower covers.

Second pic is looking forward from about the motor mount area.

EDIT you posted as I was writing. Looks like the problem was further underneath. I don't remember seeing anything when swapping out the motor mounts that caught my attention but will double check now, thanks.

CIMG3718_zpse50acb28.jpg
CIMG3721_zpse46f683d.jpg
 
It's possible the wiring harness got cooked from the exhaust leak too. Hopefully the Kooks seal better than the factory exhaust did. I previously had a leak in the same spot on the driver side that we fixed last summer.
 
Had a consistent issue at the Track yesterday. Check charging system message and battery light come on 10 minutes into session, and voltage steadily drops from 14.x to 12.x.

On cool down and driving around paddock battery light goes out and voltage slowly recovers. Leaving to idle for 5 minutes on key on I'm back to 14.x

Just went out for a drive on the street -- no issues 14.x volts. So this is either a sustained high rpm or heat related issue.

Anyone have any ideas?

Don't want to resort to the dealer as they are unlikely to replicate, and will probably challenge warranty as I'm outside 3 years and have the battery relocation kit from Steve. Don't want to drive 7 hours to the Glen on Labor Day only to have the alternator give up!
 
Black Boss said:
Had a consistent issue at the Track yesterday. Check charging system message and battery light come on 10 minutes into session, and voltage steadily drops from 14.x to 12.x.

On cool down and driving around paddock battery light goes out and voltage slowly recovers. Leaving to idle for 5 minutes on key on I'm back to 14.x

Just went out for a drive on the street -- no issues 14.x volts. So this is either a sustained high rpm or heat related issue.

Anyone have any ideas?

Don't want to resort to the dealer as they are unlikely to replicate, and will probably challenge warranty as I'm outside 3 years and have the battery relocation kit from Steve. Don't want to drive 7 hours to the Glen on Labor Day only to have the alternator give up!
I don't know Nick this seems to be one of those intermittent problems. I was getting it quite a bit for a while but not lately. Check your wiring near your headers going to the alternator to see if anything's chafed or cooked. Otherwise it appears to be one of those track related gremlins that pops up from time to time. I would get it with 13.x to 14.x volts so it's weird.
 
Black Boss said:
Had a consistent issue at the Track yesterday. Check charging system message and battery light come on 10 minutes into session, and voltage steadily drops from 14.x to 12.x.

On cool down and driving around paddock battery light goes out and voltage slowly recovers. Leaving to idle for 5 minutes on key on I'm back to 14.x

Just went out for a drive on the street -- no issues 14.x volts. So this is either a sustained high rpm or heat related issue.

Anyone have any ideas?

Don't want to resort to the dealer as they are unlikely to replicate, and will probably challenge warranty as I'm outside 3 years and have the battery relocation kit from Steve. Don't want to drive 7 hours to the Glen on Labor Day only to have the alternator give up!

Check and make sure that the nut under the main wire coming out of the alternator is tight. Over a period of time it can loosen. You won't know it until you take the nut off the top and remove the wire. Once the wire is off, make sure you cannot move the bolt/stud around. If it is loose you can tighten it. If you need an alternator, the cheapest place I have found one is summit racing. You can buy the complete boss 302 alternator kit for under $300 and it includes the tensioner and pulley, the idler pulley, the belt and the alternator. And worse case scenario, I am about 1 3/4 hours from the glen and I have a spare alternator! Mike
 
cloud9 said:
Check your wiring near your headers going to the alternator to see if anything's chafed or cooked. Otherwise it appears to be one of those track related gremlins that pops up from time to time.

06mach1 said:
Check and make sure that the nut under the main wire coming out of the alternator is tight.

Thanks Gary and Mike.

Checked both and no issues. Wiring looks like new and stud/nut were tight.

Have ordered an alternator kit from Summit to throw in the trailer. My low end voltage was consistently 12.0v at the end of 20 minute sessions, and the group I'm going to the Glen with run 30 minutes.
 

302 Hi Pro

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Black Boss:

You might want to pick up a spare battery and battery charger for the trailer as well. If the charging system goes again, it won't take long to discharge the battery under race conditions. Good luck

302 Hi Pro
 
Black Boss said:
Thanks Gary and Mike.

Checked both and no issues. Wiring looks like new and stud/nut were tight.

Have ordered an alternator kit from Summit to throw in the trailer. My low end voltage was consistently 12.0v at the end of 20 minute sessions, and the group I'm going to the Glen with run 30 minutes.
Not a bad idea to have the spare alternator Nick. I have replaced two now in 4 years. I am just saying that the last tine I was getting the message was the first track day after replacing the second alternator so it wasn't alternator related. It seems to have gone away for now. I am still on the original battery albeut it's now in my trunk :D

Last night driving home on the freeway I git a flashing CEL and P0300. I haven't had that since my first couple track days and installing the TSB O-ring. Go figure.
 
Today I noticed the split plastic wiring sleeve has melted on the wiring harness from the alternator to the battery - similar to what Gary saw on his car last year. It is the large wiring harness on the passenger side, next to the engine and is clipped to the strut strut tower. There is factory aluminum heat tape on the harness for about 8 inches near the frame rail. From there on to the battery it is just black plastic harness tape over the split sleeve. The aluminum heat tape needs to be extended another ~18 inches to the bottom of the battery tray. I have the K-member out and the exhaust manifold off and got some good pics. My car is an April 2011 build and has factory exhaust manifolds and has ONLY seen 5 track days.

The pictures were taken underneath the engine bay looking up at the passenger strut tower. The brown frame rail is at the bottom, above is the melted harness and behind the harness is the A/C suction line. The second pictures is a close-up the melted area.

AlttoBatMeltedHarness1.jpg

AlttoBatMeltedHarness2.jpg
 
Cherno134 said:
Today I noticed the split plastic wiring sleeve has melted on the wiring harness from the alternator to the battery - similar to what Gary saw on his car last year. It is the large wiring harness on the passenger side, next to the engine and is clipped to the strut strut tower. There is factory aluminum heat tape on the harness for about 8 inches near the frame rail. From there on to the battery it is just black plastic harness tape over the split sleeve. The aluminum heat tape needs to be extended another ~18 inches to the bottom of the battery tray. I have the K-member out and the exhaust manifold off and got some good pics. My car is an April 2011 build and has factory exhaust manifolds and has ONLY seen 5 track days.

The pictures were taken underneath the engine bay looking up at the passenger strut tower. The brown frame rail is at the bottom, above is the melted harness and behind the harness is the A/C suction line. The second pictures is a close-up the melted area.
Did you get the warning message or just notice it's melting?
 
cloud9 said:
Not a bad idea to have the spare alternator Nick. I have replaced two now in 4 years. I am just saying that the last tine I was getting the message was the first track day after replacing the second alternator so it wasn't alternator related. It seems to have gone away for now. I am still on the original battery albeut it's now in my trunk :D

Last night driving home on the freeway I git a flashing CEL and P0300. I haven't had that since my first couple track days and installing the TSB O-ring. Go figure.

Replaced the alternator and ran all day at the Glen today with no warning message or battery light. I'm going to order a spare for the trailer.....
 
Black Boss said:
Replaced the alternator and ran all day at the Glen today with no warning message or battery light. I'm going to order a spare for the trailer.....

I wonder if the parts are available to rebuild it? Wonder what went wrong to be begin with?
 
06mach1 said:
I wonder if the parts are available to rebuild it? Wonder what went wrong to be begin with?

I believe the voltage regulator is integral to the alternator. Given my issues were rpm and/or heat related, my guess is the regulator went bad. As I re-used the belt and tensioner, that rules out belt slippage.
 

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