How does one tell what type securities system (ie; VAT's, passkey, passlock.) came on their truck. I want to do the remote start and I was wondering if I needed the bypass kit?

I believe its passlock II on the hd's

When I did mine I bought the one with Passlock II and Passkey III combined. Its called a GMDL-BP.

So I guess I will have to fork over the extra money for the bypass, thank for the 411 folks...

Passkey is used on older GMs. I don't know what year they switched over, but I believe all the newer GMs now use passlock. It is easy to tell if you have a passkey. You will be able to see a small black resistor in your key if you have passkey. If you have passlock, your key will look like a normal key.

Passkey is used on older GMs. I don't know what year they switched over, but I believe all the newer GMs now use passlock. It is easy to tell if you have a passkey. You will be able to see a small black resistor in your key if you have passkey. If you have passlock, your key will look like a normal key.


That's right. They started the change around 1998 and up vehicles. The 03+ not only needed the passlock II bypass, but also the databus interface. Most companies now make one module to do both, and the ones that I sell are almost the same price as a single bypass module.