For those of you awaiting the outcome of this thread:
http://forums.corvetteforum.com/show...582&forum_id=1

Here is the bad news! The dealer found NOTHING WRONG!
The worst possible result. Here's what happened.

Towed car to Dealer Friday 12/23.
Demonstrated to Service person - (1). crank but no start, (2). all warnings repeatedly displaying on DIC. I'm told "Tuesday before we get to it," which was ok with me given the holiday.

Today I get the dreaded call. After sitting in the lot for 5 days, the tech got in the car and it started right up and everything was normal!

His remarks:
Found some codes - L1016 loss of PCM, U1096 loss of instrument cluster, U1255 loss of serial data, P1655 power train induced pitch. (Said they were all historical.)

Checked power supplies and grounds - OK.
Started vehicle, cleared all codes, test drove and no codes.
Operating to specs at this time.

arrgghhh! So now I live in fear that sometime in the future this gremlin will reassert itself at the worst possible time and place. (That Red, Tan, Cashmere, A6 vert in the showroom looked tempting till I saw the 63K list price ) .

So thanks to all for your advice and concerns. I'll be staying close to home with my cell phone charged and AAA card at the ready.

 

Sorry to hear about your trouble... if it happens again.. trading your problems away for a new Corvette sound pretty good to me!

VR

 

make sure the grounds on the sides of the block are clean and tight.i know if one is loose you end up with your problem.
as far as the dealer,checking this and that,i doubt it because the tech doesn't get paid unless something is found wrong,and gm will not pay diagnostic time,then gm wonders why they are in trouble.trust me,i know.i have been a tech in a dealership since i was 17.i used to work in the domestic shop[i did caddy,pontiac/chevy/olds]but gm will not pay you to fix their product and if they do,their flate rate times are not realistic that is why most guys who really know their stuff go elsewhere[i now work for audi],because you can't survive working for the big 3

 

Thanks Don. When it warms up a little I'll go through the ground cleaning process just to rule out that possibility. The three easy ones I already did and they looked pretty good actually. But the car is 7 years old and I guess it's time to do it.

 

Let me ask the stupid question that seems to cause these kinds of problems....how old is your battery? From what I've read here on the forum, a battery on the way out can cause a multitude of weird problems......or.....how are the battery cables? Are your cables tight at both ends?

 

I feel sorry for you. Intermittant Electrical gremlins are by far the worst. One problem with the newer cars is although technologically 'advanced' that means theres more stuff that can go wrong with it. Hopefully it was a one time thing and will never return (wishful thinking eh?).

 

Thanks Eric.
Sympathy is the next best thing to a cure. Right now I just can't get motivated to do any more than I already have. I really want to check the PCM connections because I'm sure they are not "hermetically sealed," and even if not leak-damaged, they could oxidize enough to cause problems. I just have to set aside a day to check that plus all the grounds...when it gets warmer? In the meantime I'll drive it to work (20 miles roundtrip) once a week and see what happens.

 

Cenzo, I had a similar issue almost four years ago at a "Stealership": I was miles out of town, far away from home, when one of my beloved C5's completely stalled, necessitating being towed to the neareast "Stealership". After administering a quick manual diagnostics, and, having noted the evidentiary symptomology, I correctly assumed that the fuel pump assembly unit had failed needing replacement. Moreover, I knew that this simple fix was covered under warranty. However, it was closing time and the car would have to remain overnight for service in the morning.

The following day, I found the Chevy advisor and tech's at this particular dealership standing around my car, all scratching their heads thinking how overwhelming the C5 is; How long the list of parts (they incorrectly assumed) that would need to be replaced, from the ignition switch and BCM, to the PCM itself; and, yet, how they grinned over the cost to me stating that possibly nothing may be covered under the warranty! This was shocking! Honestly, I could not believe the ignorance of the techs and advisor!

Basically, the incompetent azzholes left my lights on allowing the car battery to die causing the crux of the problems mentioned above. And, then they were shocked that the o.e. battery would not hold a charge! Furthermore, they damaged my front bumper while moving the car to another stall. Needless to say, after I drilled them another anus, I had the vehicle towed to yet another dealer where the fuel pump assembly unit was successfully replaced. Moreover, I installed a Red Top Optima battery, and, was good to go. Moral of the story: Inspect the battery, cables, connections, and, all grounds. And, be cautious and informed of dealership experience and service regarding C5's.

 

Since I had the same problem as Cenzo I'll post my update as well:

Corroded battery cable was the diagnosis. Stearlership did not get my car, I had it towed to Corvettes of Houston instead. I'll never take it back to the dealer again.

I had mine towed even though it started just fine, not taking a chance of the car dying in route.

Anyway, all seems to be well now.

 

....Smart choice.....

 

I feel for you as I too had the C5 from HELL that would just DIE without warning!!! . The problem got so bad that I thought about BURNING the damn thing!

Preserverance succeded and I fixed the problem!

Here is what you need to do. Some of the things sound like they have NOTHING to do with your issue but, I strongly recommend that you follow through on the check or maintenance!

1- Remove both battery terminals. Spray them out with brake parts cleaner and then a good shot od WD-40. Reinstall them and "TORQUE" them back on using a torque wrench to 11 ft/lbs.

2- While the battery is disconnected, remove the BCM. Inspect the BCM and the area where the BCM lives for signs of moisture. My BCM was exposed to moisture from condensation that drips off the black 1/2" rubber hose that connects the HVAC fan motor to the HVAC air box. I wraped the hose with a piece of bubble wrap. The circuit board inside the metal box the BCM lives in had white corrosion on the back of the board. If you have the corrosion, just whe a stiff bristle brush and some alcohol to clean it off.

3- Grounds! Grounds!!! Grounds!!!! The main cause of my problem were corroded grounds!!!! I have an hugh post on this very subject! If the dealer told you that he checked all of your grounds, He is either lying or he threw his eye ***** on the ground connections and made sure that they were still there! NOTHING ELSE!

To complely clean all of the grounds that you need to worry about will take you a good 3-4 hours.

Here is a link to the post that I made on this very subject! You will need to completly disassemble the chassis ground connectors to see if the pins inside are corroded!

http://forums.corvetteforum.com/show...ion&forum_id=1

If you have any questions, PLEASE let me know!

Bill Curlee

 

Thank you, Bill.
I'm gonna do it, I'm just waiting for some nicer weather. I too am skeptical of the dealer ground check. He claimed to have cleared the codes too, but he didn't. I don't know how codes get from current to historical, but two days and three ignition cycles after they were "cleared', I found 26 H codes and a PCM P1652 H C. My plan is to drive it close to home and see if any new codes develop - could be exciting.

 

to the same dealership that told you they couldn't find anything wrong. Make it their headache!

 

Vince

Clear the codes and drive it. Then list all of the codes that it is throwing here. That will help me generate a get well plan for you.

Bill

 

Bill, I decided to take a chance and drive it to work today.

Cleared codes.
Arrived at work (4 mi) and had a P1652 H

Cleared code.
Drove home and found P1652 H C ??

What the heck is Power train induced chassis pitch?

The drive seemed normal in every way. Maybe not enough to go on?
I'm hoping the original disaster event will happen just as I enter the garage one day.

I'll drive it summore this weekend.

Vince

 

the fault is for the diagnostic circuit between the pcm and ].the esc[suspension control] module.what's supposed to happen is when you jump on the gas or brake hard the pcm grounds this circuit so the esc controller can stiffen the shocks.the fault sets when the command and what's actually happening don't match.the pcm gets 5 volts from the esc controller.when you accelerate or hit the brake the pcm grounds the 5 volt circuit.FWIW,this code will set IF the bcm is programmed for esc and you don't have it.if you do have esc look for blown fuses[rtd,etc.],bad grounds,etc.

 

dpd beat me to the gate again!

The ECS module is powered buy the under hood electrical center fuses:

Mini fuse# 7 (RTD) , It is controlled by mini relay# 41 (RTD)

The ground for that module is G-402. I would look there first! The rear chassis grounds (G-401 & G-402) are subject to a lot of nasty envoirmental conditions (road salt, water, mud and what ever the tires kick up. Make sure that you soak the ground stud in WD-40 and be careful not to wring off the stud when you remove the nut.

Here is a picture of G-401. I dont have one of g-402 but they are mirror images of each other. The ground point is on the rear chassis frame rail in the passengers rear wheel well between the rear of the tire and the wheel well.



If you look closely, you will see a screw vise a stud and a nut! I broke mine off when I attempted to remove it and had to use a self tapping sheet metal screw. It works like a champ! G-401 is for the fuel level sensor and fuel pump and G-402 is for the EBTCM and ECS module circuits.

Bill

 

Well I guess I have a place to start. You guys are Incredible! I'll let you know what I find. The car has Magnetic Selective Ride Control, is that RTD?

Thanks,
Vince

 

 

RTD stands for ( Real Time Dampening ) Its part of the Selective Ride Control system