Greetings from a Vette newbie from the great white north.

Recently came across this car for cheap as the original owner decided not to fix it and thought I would give it a go since the car is in pretty good condition. Learned a fair bit about the car so far and have dealt with some obvious issues, however a bit stuck with the no start condition.

I seemed to have narrowed it down to the BCM and a VATs issue - fun times that was getting it out. I think even funner getting it back in. May have to pull the dash unless someone knows a trick?

Basically what I have done: I can get the starter to crank the engine however there is no fuel. Went through all the combination using a VATS integrator with no luck, so I am pretty sure there is some sort of hardware failure in the module. Or if someone else can suggest something else?

In any event, anyone have experience with repairing these and any suggestions what to look for? Are the BIN file available for download someplace (I so far have been unable to find them - just ECM ones). This is a 16159188 with the AXAK VATS. That being said what is the method that is used to program these since they are not MEMCAL or EPROM that I am use to (the AXAK IC is solder to the board vs a socket, but that isn't too much of an issue).

Edit - hmmm, after some reading, looks like I may be barking up the wrong tree - it looks like the VATS can be disabled in the ECM - regardless, I like to try and solve the issue with the BCM.

 

Assuming you've registration for the car you might visit a GM Dealer and ask them to do a key code request. Generally the VATS code is retrieved with the ignition & door key. Most dealers charge for this service but if you mention OK but only if the VATS code is supplied with the request that might be a strategy. Did the Interrogator provide you with CRANK or you just jumped the starter for CRANK? Putting it back is certainly no pleasure. Are the cables long enough that you can connect the CCM to test with no issues?

It's been mentioned that '90+ with CCM:

When using an Interrogator you need to employee some strategy, you can do I believe 3 requests with the initial timing interval (4 minutes) and after that you need to wait 10 minutes. Did you maybe do your Interrogator timing delays incorrectly?

 

Thank you for the reply, and to answer your question and maybe add some more details:

Have the OEM keys and have the bill of sale, not registered yet as I didn't see the point without it running (does have fire and theft insurance though).
Have the key code (XB - so 2.370ohms)
Original owner actually had the car at the dealership to fix this problem, but didn't want to pay for repair (the dealer quoted the BCM and something like 15 hours labour). It was basically picked up at the dealer and brought home.
Starter physically jumped and the car did fire until it ran out of fuel.
Yes, I waited the allotted time between using the Interrogator (actually longer) - not my first rodeo at doing this. Just new to the whole Corvette thing.

Cheers,

 

Reach out to @-=Jeff=- and mention your CCM issue. He might actually stop by anyways, but he might be able to help you with your CCM/BCM issue. If you had access to a used, the car cranked and runs with it he can correct VIN and mileage for you. Your where?

*** GM also has a rebuild yours program that I believe is still active You surrender yours, the dealer sends it to GM and if it can be they repair and return. If it can't be it's returned to the dealer 'NO CHARGE'. Is the dealer wherever you're located familiar with the service? Seems maybe since they quoted a $$$. I believe I have a form that was used, If I do I'll post it maybe you ask another dealer if they're familiar with and even if it's a service still available.

 

Yes I can reprogram the CCM or program a replacement. I can put it on my bench to check some of it out but I can't do any hardware fixes as schematics I have not found yet.

you are required to have the VATs programmed in the CCM, you can program the ECM to ignore VATs but I don't believe the CCM ignores it.

 

This is the GM form for the 'Module Exchange Program'

 

Thanks for the information so far.

1 question - say I bypass the VATs in the ECM, how does this affect this unit if the VATS in it is not working? What is "disabled"?

If you program a replacement, what kind of dollar value am I looking at? I am not convinced a reprogramming will fix this as why would that fail? Although, since I am still learning, I guess it is possible, but what are the chances?

 

The passage above probably has a big relation to not being able to find a value with the interrogator. I would start from scratch and go through the values again.

 

The VATS being disabled in the ECM will not do you any good. The CCM and ECM do several checks back and forth to validate the security/start enable sequence. If your CCM is not receiving the correct communication from the ECM, it will not work.

 

So then this product must still allow some sort of communication?

https://www.pcmofnc.com/product/vats...p-1986-1993-3/