CPL Automotive Lock & Transponder Systems 2 — Questions and Answers
Question 1: What does the term 'rolling code' refer to in remote keyless entry systems?
- A fixed code transmitted each time the button is pressed
- A code that changes with every button press to prevent replay attacks (Correct answer)
- A code that rotates based on time of day
- A code used only during initial pairing
Correct answer: A code that changes with every button press to prevent replay attacks
Rolling codes (also called hopping codes) change with every transmission, preventing thieves from capturing and replaying the signal.
Question 2: Which tool is most commonly used to decode automotive lock bitting without disassembly?
- Plug follower
- Impressioning file
- Lock scope or borescope (Correct answer)
- Plug spinner
Correct answer: Lock scope or borescope
A lock scope or borescope allows a locksmith to visually inspect the wafer or pin positions inside an automotive lock to determine the bitting.
Question 3: What is the primary function of a VAT (Vehicle Anti-Theft) resistor pellet in GM ignition keys?
- It stores the VIN number electronically
- It provides a specific resistance value the vehicle ECU reads to allow starting (Correct answer)
- It powers the transponder chip
- It activates the immobilizer relay
Correct answer: It provides a specific resistance value the vehicle ECU reads to allow starting
GM's VATS system reads the resistance of a pellet embedded in the key blade; an incorrect resistance value prevents the engine from starting.
Question 4: When cutting a high-security automotive key with a sidebar, which additional dimension must be accounted for?
- The key head thickness
- The sidebar warding cuts or milling (Correct answer)
- The bow shape
- The key material hardness
Correct answer: The sidebar warding cuts or milling
High-security keys with sidebars require additional sidebar cuts or milling on the key blade that must match the sidebar pins inside the lock.
Question 5: A customer's transponder key starts the car sometimes but not always. What is the most likely cause?
- Wrong key bitting
- Weak or failing transponder chip (Correct answer)
- Incorrect EEPROM programming
- Damaged ignition cylinder wafers
Correct answer: Weak or failing transponder chip
Intermittent transponder failures are commonly caused by a damaged or failing chip that only communicates with the antenna intermittently.
Question 6: What does 'cloning' a transponder key mean in automotive locksmithing?
- Cutting a duplicate key blade
- Copying the transponder's ID to a new blank without accessing the vehicle's ECU (Correct answer)
- Resetting the ECU to accept a new key
- Generating a new cryptographic seed
Correct answer: Copying the transponder's ID to a new blank without accessing the vehicle's ECU
Cloning copies the transponder's fixed or encrypted ID to a compatible blank chip, allowing the new key to function without dealer-level ECU programming.
Question 7: Which automotive door lock actuator type uses a rack-and-pinion mechanism driven by an electric motor?
- Solenoid actuator
- Vacuum actuator
- Motor-driven actuator (Correct answer)
- Pneumatic actuator
Correct answer: Motor-driven actuator
Motor-driven actuators use an electric motor with a gear reduction and rack-and-pinion assembly to move the door lock linkage.
CPL Automotive Lock & Transponder Systems 2
What does the term 'rolling code' refer to in remote keyless entry systems?