Greetings everyone! I've lurked here for quite some time but this is my first post.

I recently bought a C6 Grand Sport. The previous owner told me he had intermittent electrical issues starting that he had resolved. He said that there would be no power at times so car wouldn't even attempt to crank.

He replaced the starter, battery, battery cables, Body Control Module, electronic receiver and key FOB. From what he said, replacing the fob and receiver fixed the issue.

I just experienced what seems to be the same issue today. After running several errands where the car had started up multiple times without incident, I was stranded in a parking lot unable to start. The car seems to recognize the FOB in the sense that I can open the door but when I press the push-to-start nothing happens. No lights on the dash, no crank, nothing aside from maybe a very faint click that comes from near the aftermarket stereo head unit.

I fiddled with the battery cables and several fuses and attempted to start a number of times over the course of about 30+ minutes unsuccessfully. It finally started. I can't pinpoint anything I did differently that allowed it to start versus the other attempts.

Any other C6 owners that have experienced similar issues? Any recommendations?

 

First off what year is the car ??…if only the “ passive entry” is working but not the “passive start” that doesn’t seem to be a FOB issue or the RCDLR which is the module above the radio inside the dash and allows that passive entry/passive start or PEPS as it is sometimes called to function…do you hear a series of “clicks” and not just one click coming from it as you mentioned ??…when it is not starting do you have a ignition function ???…ie the start button can be placed in ACCY mode or run mode where you hold the button of the start button down for about 5 seconds and the green start light illuminates ??…sounds like maybe a weak battery and you should have it load tested anyway as the first step in trying to find out what’s wrong…maybe even high resistance in the starting circuit either on the positive or negative side of the starting system…you fiddled with the battery cables but you must also fiddle with the other end under the car…with a simple test light you can quickly check if it’s on the ground side of the starting circuit…there are some tests we can do at the crank relay but if you are not mechanically included it may be best to take the car to an automotive electrical specialist as they would be the best one to diagnose this…starting issues can be problems with the starting system or a communications issue unfortunately 99.99% of shops and even dealerships don’t have the faintest idea how to diagnose those…an auto electric shop may.

 

It's a 2012. I don't believe it's a weak battery because it's less than a year old and when I finally got it to crank it started right up.

It might be a short series of clicks I'm hearing and not just one. It is very faint however. I didn't have ignition function when it wasn't working either.

 

To have ignition function the RCDLR (I think that is the electronic module you were referring to) and the BCM have to communicate with each other so maybe it's a comm issue...do you have a scan tool that can read all of the cars modules ??...if not do you have a DVOM and know how to use it ??...if no to both seek out an auto electric specialist...we can't give you a firm diagnosis over the Internet for something like this...it's not going to be a blown fuse.