It is the VAT system, thinking your are a car thief. Repair or replace the system.
I checked fuses and replaced blown fuses and now it won't start.
Is this an automatic or manual transmission?
== ==
If your headlights, horn and everything work, I would have the ignition switch checked out. Make sure you checked all ingition fuses and relays first.
Check ignition relay. Jump the battery directly to the starter and see if the starter is any good.
Connect the positive cable to the positive battery post on the donor car and on the Corvette. Connect the negative cable to some metal part of each vehicle, such as the engine. Be careful of the fan blades on each car. Let the donor car run for approximately 15 minutes to put a slight charge in the battery on the Corvette before you attempt to start it. Start the Corvette and as soon as it starts disconnect the battery cables.
To get a 1990 Corvette to start if it turns over and the battery is good, check to ensure the fuel filter is not clogged. You also need to ensure it has plenty of gasoline.
Check all earth wires from battery to engine and earths from body to engine
You may need to have your starter checked. If the radio comes on, then its not the battery. Does the truck make a clicking sound when you try to turn over the engine. If it makes a click -click noise when you try to start, then its not your starter.
Sorry but your question makes absolutely NO sence whatsoever! do you mean that you have already Changed-(with an A, try using spell checker next time pal!) your battery with a new one and your vehicle still will not start? Have you checked ALL fuses and relays related to battery, starter, altenator, ignition and fuel pump? Have you checked ALL spark plug wires? distributor cap, spark rotor or coil pack wires? Have you checked for fuseable links and if your vehicle has any are they bad?
Check electrical spark, if you have good fire, you can put a few drips of gas or spray some ether in to determine if it is a fuel issue, if it runs on ether, then try rotor and cap.
have you checked the relay on the starter? and check the wire that runs from the started relay to the starter.