How do you get the codes from computer of a 2003 Chevrolet Impala?

For the 2003 Chevrolet Impala, there is no code retrieval process. Rather than a code, you will retrieve a Passlock security code which enables the powertrain control module (PCM) to recognize the ignition key and allow to vehicle to start.

- Turn the ignition from off to run eight times within ten seconds to retrieve the security code.

- Do not start the vehicle.

- Leave the ignition on.

- The anti-theft indicator light will flash several times.

- Count how many times it flashes.

- The number of light flashes is the first digit of the security code.

- Turn the key to the off position.

- Repeat the process to find the remaining four digits.

- Write down the security code for later use.