I have searched this forum high and low for anyone experiencing something similar to the problem I have been dealing with for the last month.
For the sake of writing a book I will summarize my situation the best I can.
I get into my 08 Automatic C6 Corvette make sure my foot is on the brake pedal and push the green start button and the lights on the dash dim, service engine light illuminates. After about 10 seconds the gauges sweep, I push the button again and the same process happens over and over again. Once in awhile the car will crank and start but less times than more. I hear relays clicking on the floor of the passenger side, and some other noises behind the dash but the car does not crank. I get my code reader and the only code I have is U0100 Lost Comm With ECM PCM A.
I try everything I know what to do. I take my 18 month old battery back to advance auto parts and they test it twice and tell me the battery is putting out like new. I clean the battery terminals. Check all twelve grounds in the car that I know about. I check as much of the wiring harnass as I can see. I check all of the fuses and relays that are under the hood and in the BCM. I already have a new alternator that is only 4 months old but I also check the output of that. I check as many of the connections that I can get too fairly easily that are under the hood. I did see a TSB on my car for a U0100 code being the 16 pin connector that goes into the transmission. I got a mirror and light, crawled up under the car but did not see any of the wires pooched out of the connector so felt like this was not the problem with my car. I am sure I am forgetting several things I checked but I did do all of the above over the last month. I really do not want to take my car to the dealer expecially with this only code. I feel they will have a hayday with my wallet.


I am trying to think of everything and anything that I have done or purchased for my car fairly recently and the only thing I did was install a new pioneer avic-8200 radio. The radio install went well for the most part. I installed it using the factory power/wiring harnass. I also installed a backup camera that came with the radio. Everything works well with the radio. I have been going crazy trying to figure out the no crank and code situation on my car, yesterday I figured to disconnect the rdo 15 amp fuse in the passenger footwell of my car and wallah.... Car has been starting just fine. I have started the car at least 5 times since removing the fuse and the service engine light has gone out. I have checked for current codes and the U0100 code does not come up anymore.
Has anyone heard of such a thing? I did not read about this anywhere and feel like I got real lucky figuring this out. I also felt I needed to post this experience on the Corvette Forum. I have been a long time lurker before signing up and must say that this forum has saved my butt on more than several occasions.
I feel I will drive and monitor the car before trying to resolve the radio issue.
If anyone has any ideas or thoughts I would love to hear them. So far I am really happy to have my car back.

 

I know this is an old thread but the same thing happened to me today.. I was in the process of flashing a tune and the HP Tuners interface would not connect to the ECM and said "unlicensed vehicle" which was strange. I tried started it and nothing...same DTC code U0100 and there is no crank or start. About 10 seconds after pressing the start button the gauges sweep and then the DIC runs through a series of messages..."service active handling, service traction control, service fuel system, low fuel. I tried pulling the radio fuse but that didn't work. I also recently installed a radio and backup camera so thought that was it once I saw your post but it wasn't. All fuses seem ok, and bettery is less than a year old. It was running fine and I shut it and now I'm dealing with this. Anyone else have this issue happen? How did you fix it?

 

In my last reply where I thought my car was fine it ended up very short lived. A day or two after claiming my car was fixed I was having all of the same problems with No Crank, No Start and the U0100 Lost Comm With ECM PCM A.
Long story made short I had my car towed to the Chevrolet dealer in Manassas Virginia. They had the car for about one week before I heard back from them. They told me my car was going to need a new ecm, bcm, and push start button. When I asked them what the cause was for needing all of these new parts they could not tell me why any of this has happened.
I told them to go ahead with their diagnosis and to only run the car for 15 to 20 seconds to verify these parts were the problem because I have a tune in the original ecm from east coast supercharging. They did do this. They called me told me to come get the new ecm in order to send the ecm to east coast which I did. East coast got the ecm in two days and had the ecm back to me in the same amount of time. I did the tuned ecm back to the Chevrolet dealer for them to install and the car has been fine for the last year except for one problem which the car did not have before any of all these problems. The Service electrical system comes up in the DIC every 10 minutes. I hit reset it comes back in 10 minutes. I am just happy my car starts and runs. This all took place over a 3 month period of time, quite the nightmare. Total cost to fix $2,200.00
Good luck! If you have any comments, questions, or concerns you would like for me to answer I will do my best to help.

 

I just submitted quite a lengthy reply and cannot find my post anywhere. I am trying this again. As you can see I have not posted much here so am trying to figure out how this works.
To make a long story short I ended up having my car towed to the Chevrolet dealer in Manassas Virginia. They replaced the bcm and push button start switch. Then they replaced the ecm. Total cost $2,200.00
This did fix my U0100 Lost Comm With ECM PCM A. Car cranks, starts, and runs fine except I have Service electrical system in the DIC that pops up every 10 minutes. I did not have this problem before getting all these parts replaced.
I did have to send the brand new ecm back to East Coast Supercharging for them to upload my tune into it before allowing the dealership to install it.
I hope this posts!

 

 

Update. I took the battery out for a few hours and put it on the charger. I also crossed the positive and negative cables just before putting the battery back in. Tried to start it but same issue. Then I tried loading a tune and low and behold, HP Tuners connected. Once the tune was loaded it fired right up. Phew!

 

Hi,
Thank you for this video. It was very interesting and informative. I watched the whole thing. I also wondered if you where the instructor of the video because I noticed "obs" in your screen name and the instructor of the video David Hobbs which also has "obs" in his name.
I am curious to why after the Dealership replaced the ecm, bcm, and push start button and I have the radio installed with backup camera, the RDO fuse is installed that the radio works, backup camera works, and the car seems to work again (crank, start, run) other than the "Service Electrical System" message in the DIC. After watching the video and trying to think things through in my head their are so many variables.
Maybe I shorted something out when installing the radio that killed the ecm/bcm? I was very careful and purchased all harnesses, modules for the radio through Crutchfield. I certainly am not the first owner of an 08 C6 Corvette to install an aftermarket radio in their Corvette.
Before having my car towed to the Dealership I completely uninstalled the aftermarket radio leaving no radio in the car in order to eliminate it from the problem.
I talked to the technician that installed the new parts when I went to pick up the New ecm to send to East Coast to install my tune. He said he ran the car for about 30 seconds and the car functioned flawlessly with no codes or messages in the DIC. There was no "Service Electrical System" message in the DIC.
I received the ecm back from East Coast, delivered it back to the Dealership and left. I got a call from the service advisor to come pick the car up but their is a "Service electrical system" coming up in the DIC. I went to pick the car up and talked with the technician for about a half hour. He said he ran 38 tests with his Tech 2 and 2 tests failed. Code P0103 Mass Air Flow (MAF) Sensor Circuit High Frequency test failed. Called East Coast, Doug said this is because he tuned my car using Speed density tune and would not cause Service electrical system message. Second test I show - Digital Radio Receiver U1000 Class 2 Data Link Malfunction. Technician said installing radio would eliminate DIC SES message. Doug at East Coast said this would not cause SES message in DIC.
Doug (Tuner) at East Coast Supercharging said he flashed the New ecm with the exact tune he saved that put on the original ecm.
I was wondering if maybe in the tune Doug uses Service electrical system message to appear in the DIC vs Engine Light in order to pass inspection in certain circumstances. My state will not pass you if your engine light is on. They only mentioned the Service electrical system message on the DIC but my car passed inspection recently August this year.
I hope "Turboffr" similar problem to mine does not run him in circles for three months or cost him what I ended up paying.

 

 

Hi, I have a 2007 vette and I am experiencing the exact same issue. I get no crank and no start intermittently. I have a manual transmission and i realize sometimes when this happens and I push the gear lever to the left the car fires up. I had to tow it to the dealership and they said they cannot fix the issue because I have aftermarket wiring in the car. The only aftermarket stuff i have in the car is an exhaust cut out and an aftermarket radio. Any help will be greatly appreciated.

 

 

Thank you, I will do that when i get back to the mainland and keep you updated. I am in Japan for work right now. The dealership told me this when I was already here. I will also pull the stereo and see if that fixes the issue.

 

 

jon,
i did not check that but i will as soon as i get back. Thank you.