cbgpe

Just had this trouble code come up on my D I C
It came and went 3-4 x at highway speed. The connections on the alternator seemed tight & OK
Ran a scan and no codes came up. It is at the dealer will let everybody know what is up. The battery voltage when the car is running is 14.0-14.4
volts. So the alternator is working. The battery did not seem to be up to snuff however about 20 minutes with the key on doing the scan flattened the battery to the point where it would not crank... Car is kept on a trickle charger when not in use.

Foosh

Bad battery is the most likely cause.

cbgpe

Would be pleased if it is just that simple.

cbgpe

The dealer says the battery check out as good.
They are making noises about the car not being stock and warrantee issues. I don't see how any engine mods using the stock engine management system could cause "electrical" problems

Foosh

Uh oh.........didn't know you modded..........nevermind.

cbgpe

The dealer could not find the "problem" lots of codes but when cleared would not reappear. They had the car for a few days. Change the battery anyway. Took the car back took it on a trip 70 mile into the road trip "service electrical system?

Exterminator

What are your mods?

cbgpe

Vette Doctors did the work , cam milled heads, 11.5 to 1, long tubes air inlet kit tune. They have not had any similar problems. The car runs fine no other issues . We have a local mechanic who does trouble shooting for the local dealers when they cannot figure things out. The Z will be on his door step monday
Will let everyone know what he finds.

Exterminator

There is no apparent relationship with your mods and an electrical/charging system issue. The dealer has no legitimate basis to deny warranty coverage for these mods.

Foosh

There may be no "apparent relationship," but wires could have been disrupted by the work he describes, including header installation. Moreover, many tunes change the temps the fans come on, etc.

I have always believed in the old adage, "if it ain't broke, don't fix it." Every time you modify anything, you run the risk, HOWEVER SMALL, of messing up something else.

Halltech

The problem is likely your headers melting the O2 wires. I don't know what brand you have, but I have seen this twice before with ARH headers.

Fix the bad wire, and replace the blown fuse.

Jim

Exterminator

I agree totally, however I was referring to the legal justification for denial of warranty under the Magnuson-Moss Warranty Act. It would probably be difficult if not impossible for the dealer to establish that the listed mods affected the electrical system. I would not want to be in the situation of needing to prove that my mods didn't affect a warranty repair issue. I haven't modded my car for this reason.

vette67

I had the same alarm on the DIC while at the NCM and fortunately got to discuss it with the Quality Clinic guys and found that there is a bulletin on the alternator. Seems at high rpm the fan bladesin the alternator flex outward and hit the stator windings causing a momentary drop in the voltage. Just had the altenator replaced today at the dealer with no complaints. Didn't notice a recurrence of the problem on the way home.
Paul

LS7 ZO6

ARH here & no problems.
Jim what headers do you run..

PetaVette

Mine came on many times when i first bought the car. one night it came on and the HUD freaked out and the radio lost its channels. I figured the car was going to quit. It didn't and when i took it in the first time they said nothing was wrong with it.They said they tightened the belt and checked out the system. It took 2 days. The next visit they replaced the alternator. That didn't help and the next visit they replaced parts of the computer module. That took almost a week but they were repairing my roof. problem seemed resolved. Then I put ARH.Haltech F1.ported TB and port matched intake and tuned it. Walah! the "the code came on again" Now it comes on occasionally and when it does the horn won't work.weird huh?? I'm not taking it back to the dealer they have no clue as to why it happening. But in my case their seems to be a gremlin in that part of the computer that controls the dash ect It doesn't bother me that much. sometimes I'll drive it for 2-3 days and nothing will happen. its a garage queen anyway. But if it could be the O2 wire I could have that checked out by my tuner.

outnumbered

That is what mine did. The tech replaced the horn fuse and all has been well since. 8 months and counting.

He explained in a technical way that some of the electronics connect together between the horn and sensors or something to do with the alternator. It was above my head, so I really didn't get it all. But he fixed mine.

I know a lot is above my head.

PetaVette

Let us know...............thanks

PetaVette

THANKS I'll replace my horn fuse tonight............Theirs nothing about this car that i understand other than it hauls A$$

Chevtech

Here you go:
Subject: Service Charging System P0621 DTC Stored - keywords alternator battery charge dic generator gauge light low ls2 ls7 voltage #PIC4402A - (04/11/2007)



Models: 2007 Chevrolet Corvette




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This PI Supercedes To Include Looking For Short On Generator Bracket. Please Discard PIC4402.


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The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
Some customers may comment of a "Service Charging System", "Service Electrical System" and/or a "Battery Voltage Low" message on the DIC accompanied by DTC P0621 in the PCM. This may be the result of a shorted wire on the generator bracket or a cut in the stator winding that is caused from high engine RPM, usually because the engine hit the rev limiter. The internal fan is flexing and when it does flex, it comes into contact with the winding. A new generator may do the same thing if the engine is placed against the rev limiter.

Recommendation/Instructions:
Inspect circuit 225 for a short to ground on the generator support bracket, where indicated in the picture below. If no wire concerns are found, replace the generator with current SPO stock.

outnumbered

So, it sounds as if this short could blow the fuse?

I don't recall hitting the rev limiter at the time this happened to mine.

I will save the info for my tech in the event it should happen again.

Thanks for the info.

Dan