During a period of the 1980’s and 1990’s, GM introduced a security feature on many vehicles called a VATS chip. These keys were generic single or double sided key blanks with an integrated resistor. The ECU of the vehicle would require a determined resistance in order for the vehicle to start. The key, with an integrated resistor, completes the circuit of electrical current from the ECU out to the ignition and back. These VATS keys were an introduction to a new wave of security features in vehicle keys.
VATS keys were offered on a wide range of vehicles. The key blanks are available in two keyways; either single or double sided. The single sided keys all utilize a single keyway, and the double sided keys are also all of the same keyway. The resistance in either key was numbered 1 through 15.
DISCOVERING VAT NUMBER
There are locksmith tools offered that are able to either read the VATS key blanks or read a vehicle that no longer has an existing key. One of these tools is the VATS Interrogator. This tool has a probe that attaches to a mechanical key blank. When inserted into the ignition, the VATS Interrogator is able to switch between all 15 VATS numbers until the correct resistance is found to start the vehicle. Another tool is theVATS Reader which reads VATS key blanks to display the resistance number.
VATS Keys may not be in use any longer in vehicles, but many locksmiths and technicians will still encounter many of these cars on the road that need servicing.