I have a 2000 Corvette. the check engine light came on a couple of days ago and today I took it in to the dealership for an oil change. They wanted $150. For a diagnostic test. I said no I can read the codes myself. When I got home in the driveway the car went crazy. Every light in the dash came on even the windows wouldn’t operate. I turned the car off and started it back up and everything was fine. Any ideas?

 

I don’t know I didn’t read them because everything went away

 

Go read them again. The codes will be stored as a "H" file meaning History.

 

This is a shot n the dark but considering it's a 2000 as is mine, check the battery tray for signs of corrosion or deterioration.

 

Sounds like a classic intermittent serial data bus issue !!

 

I don’t want to sound dumb, but I don’t understand that. What does that mean?

 

All the modules on the car “communicate” with each other via a single wire data bus wire and if that wire gets back fed with a power or a ground what you are seeing happens.

 

I have a window valet plugged in and every so often it goes crazy and does some weird stuff. I unplugged it this morning to see if that would change anything.

 

If this “gadget” is plugged into your DLC don’t plug it in…keeping something like this plugged in can cause a lot of issues with the cars communication…there is a TSB for this !!

 

I have a window valet and leave it plugged in all the time. Has not affected anything. If its failing in some way it might affect the databus. Lots of people have one installed. Easy to test if its a problem by leaving it disconnected and seeing if the car still goes crazy.

 

I don’t know if that is the problem but I’m leaving it disconnected and see

 

Sounds like a typical ignition switch failure. A clue is the shut down and restart without symptoms.

 

I had this same thing happen last week for no apparent reason. I have no 3rd party modules connected to the DLC, so that wasn't my issue. But for me, on this particular day, everything was fine until I got the car moving / was running for more than a few minutes. That's when it "went crazy". After driving it 57+ miles home this way and letting it cool down, driving it the next day it was like nothing ever happened. Link to my post on this subject here.

Long story short, the info the DIC displays is completely dependent upon all the VPW bus modules being able to communicate as intended. If one of those modules has an intermittent power connection or some other fault, it can crap all over every other module on the bus because they "talk" over the same wire. This is commonly referred to as asynchronous serial communication.

I'm reciting this from memory, but from the factory C5s have 9 different modules that share the class 2 / VPW bus. In no particular order:

1) PCM
2) BCM
3) ABS / EBTCM
4) HVAC / CLIMATE CONTROL
5) "RADIO" / ENTERTAINMENT
6) RDCM (right door control module)
7) LDCM (left " " ")
8) SCM (driver's seat control module)
9) SRS (airbag / supplemental restraint system)

This (class 2 VPW) is a primitive form of CANBUS, and it's not very difficult to make one of the modules malfunction enough to bring the whole thing to it's knees. FWIW.

 

You can try to remove the starconnector for door/seat modules and see if your car stop behaving crazy .
This act disconnect the serialbus to these three modules and if any of these modules or serialwires are broken or partially broken these alarms
your serial databus problems should end . But door/seatmodules will not work while your doing this check .
This starconnector has three wires as shown on the schematics below
(If you disconnect the other starconnector with more wires your car would no be able to start because the PCM/BCM are disconnected from each other)

 

Took it for a spin today a little bit of a cruise and everything went well. Didn’t throw any codes or anything like that just was fine so we’ll see.