Help! Replaced battery & theft deterrent

[i2ibud]

Apologize in advance for a noob type question, but I'm stumped. Just replaced a dying battery, now I can't reset the theft deterrent system. After connecting the new battery the alarm sounds but goes silent after a bit. Unlocking the driver's door with the key activates the alarm again, and I can't silence it by putting the key in the ignition or locking/unlocking with the manual door lock. Car will not start.

Bought the car used, and I believe it's the OEM theft deterrent system, but I'm not sure. Car also has Lojack Early Warning, which I don't believe is related.

Any help is greatly appreciated.

EDIT: Car is not equipped with RKE.

 

[Red Vette]

First question is did you replace the battery with the correct one? You need a 78 series battery, not the 76. Secondly, what is the torque on the battery clamps on the terminal? Second, you need 11 ft lbs of torque for the system to operate properly. Many vendors sell the 76 series for corvettes when the 78 series is needed. Check your owner's manual for the exact series replacement.
Barrett

 

[redvett]

What year? :-0

 

[i2ibud]

Sorry, it's a 2000 coupe. Battery is a 78.

 

[redvett]

Sorry, it's a 2000 coupe. Battery is a 78.

All C5 Corvettes have RKE and Theft deterrent systems as standard equipment. Your problem is in the aftermarket system. Unhooking the battery should reset the system but make sure the reconnect is direct and not an on off connect.

 

[i2ibud]

Thanks, redvett. As I said I bought the car used, never got a remote fob. And I'm unsure if there's an aftermarket system installed, I'll have to poke around under the hood.

So, if I understand, even if I don't have an RKE fob the OEM theft deterrent should reset once the new battery is installed, and the alarm should not go off when the driver door is opened with the Passkey? The fact that it's not indicates that it's not OEM?

 

[redvett]

Thanks, redvett. As I said I bought the car used, never got a remote fob. And I'm unsure if there's an aftermarket system installed, I'll have to poke around under the hood.

So, if I understand, even if I don't have an RKE fob the OEM theft deterrent should reset once the new battery is installed, and the alarm should not go off when the driver door is opened with the Passkey? The fact that it's not indicates that it's not OEM?

The passkey is only read by the column not the door lock cylinder.

 

[i2ibud]

Thanks again for your patience, really appreciate it. I know the Passkey isn't read by the door lock, however, prior to installing a new battery, with the theft deterrent system arned, I could unlock the driver's door with the key and the alarm didn't go off. Now the alarm goes off immediately when I use the key to unlock the door, and I can't reset it. Is this the expected behavior for the OEM theft deterrent system? If so, maybe I'm using the wrong sequence to reset the alarm, could someone describe it for me? Shouldn't inserting the Passkey in the ignition silence the OEM alarm? And could someone describe the sound that the OEM alarm makes? Is it just the horn or is it multi tone?