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I purchased my 08 C6 (6 speed) last September so I am a bit of a rookie. My electrical system seems to go berserk either at start-up or within a couple of miles of leaving the driveway. Starts with the yellow key lock warning light and a service handling system warning. From there it progresses to all the gages flashing like a pinball machine or going "dead" and rotations through all of the service warning messages. Sometimes it just won't start for a while. When that happens, I hear an "electronic noise" somewhere behind the glove box, it seems. The local dealer seems to just want to reset the computer and hand it back. Now convertible weather in KY and i'm missing the joy of being a new owner cruising around. Anyone see these problems?
One of the first things a new owner will learn is that the C6 is VERY sensitive to a failing battery. The car has a lot of electronics and there is always a slight, but steady, draw on the battery when the car is not running. You did not provide any information on the health or status of the battery, so start there.
If you have an automotive voltage tester, check the battery voltage with the car not running. Should be at 12.4v or higher. A fully charged battery should register at 12.6v or higher. (If your battery is failing, the static voltage will be below 12.4v and you should replace it.) Start the car and check again. With the alternator charging you should get about 14.5 volts at the battery. This will be a quick check to confirm that the charging system is healthy.
Also, be sure to get a reliable battery maintainer to keep the battery charged (but not overcharged) while the car sits.
Hope this helps and be sure to let us know the ultimate resolution as this will assist others.
Following all the much appreciated, great advice, results were 12.6 voltage at rest and 14.4 when running. Glad to eliminate battery and alternator. Battery was installed in May 2021. (Was it installed properly, "registered" as the manual calls it - ??). Described problem is still the problem and seems even worse. Doesn't want to start without using the slot and berserk gage behavior ongoing. After getting it going yesterday, drove a couple of miles around the neighborhood, runs like a dream once going. [So good when its good.] Don't know if this means anything, but after the short drive the battery which was at 100% at the beginning was down to 84% when I rehooked the maintainer. That surprised me.
Again, being a novice, it looks like I have an extra component. There is a rocker switch under the dash on the passenger side that is getting power from a fuse box plug-in. Where it goes, I hav no clue, but it seems to affect how the engine runs - incredibly smooth at one setting and nosily backing-off at the other.
Looks like I'm still looking. Many thanks for any pointers.
Chasing down an electrical problem can be frustrating. Your symptoms could be the result of issues with the BCM large blue connectors found within the passenger footwell. Disconnect your battery and then disconnect each of these blue connectors looking for bent pins or corrosion. Clean them with electrical contact cleaning spray, spread a small amount of dielectric grease on the two halves and reconnect them. I believe there are 2 to 3 of these blue connectors. Once completed, reconnect your battery. Hopefully, this may help. Otherwise, you will need to start chasing down ground connections, possible burnt pins in your engine fuse box or other major module connections for inspection & cleaning.
As to the passenger-side rocker switch, post a picture of the connections to the fuse panel. This may be a switch that would control the exhaust valves to manually open/close them, if your vette has the NPP option. If so, should only affect the amount of exhaust sound. After review of your PICs, someone may be able to identify if not an NPP switch.
BCM, not only the blue connectors, but Red connector as well when it comes to cleaning connections on the BCM.
Myself, since the main power to the BCM is out of the engine fuse box, will start with it,
And since the voltage on the dash and DIC is telling the voltage of the ECM that the BCM is sending to it (not at the dash), ecm connectors get a good cleaning to start with as well.
Also, BCM and ECM had their own ground wires to chassis points, so make sure to clean and check them as well.
As for last one, alternator cable to battery cable connects at the starter solenoid, so want to check that connector, as well as the batter ground cable to engine block right above the starter.
And yes, that is the terminal that the two wires connect to, that is broken off the starter solenoid in the photo. So car may be getting power when you hit the starter button, but no way in hell that the starter is every going to turn over since it not getting any power to begin with.
If such is the case with broken starter solenoid terminal, then new solenoid to put back on the starter, is less than $20.
ACDelco p/n 10503939 or Waiglobal #66-161
Many thanks to both GDMoore01 and Dano523. In a couple of days, I have become much more knowledgeable re the problems and a much more confident consumer of dealer / mechanics services. I thought this forum might be valuable but it has exceeded my expectations substantially. Thanks again for being so forthcoming and quick to respond. I have an appointment set up with a list of great discussion points. Harold Butler
Many thanks to both GDMoore01 and Dano523. In a couple of days, I have become much more knowledgeable re the problems and a much more confident consumer of dealer / mechanics services. I thought this forum might be valuable but it has exceeded my expectations substantially. Thanks again for being so forthcoming and quick to respond. I have an appointment set up with a list of great discussion points. Harold Butler
2008 C6 electrical issues??
