CAL - Certified Automotive Locksmith Ignition System Servicing Questions and Answers 1 — Questions and Answers
Question 1: A customer's key turns freely in the ignition of an older Ford vehicle but does not engage the starter or power any accessories. The key feels 'loose' with no distinct detents. What is the most likely component that has failed?
- Transponder chip
- Ignition lock cylinder
- Ignition actuator pin (Correct answer)
- Body Control Module (BCM)
Correct answer: Ignition actuator pin
The ignition actuator pin is a common failure point in many older Ford models. It is the mechanical link that translates the rotation of the lock cylinder into the linear motion required to operate the electrical ignition switch. When it breaks, the key and cylinder will turn without resistance, but the switch is never engaged. [14, 16, 29]
Question 2: When servicing an ignition lock cylinder that needs to be removed from the steering column, what is typically required to depress the retaining pin or wafer for removal?
- The ignition must be in the 'LOCK' position.
- The key must be turned to the 'ACC' or 'ON' position. (Correct answer)
- The steering wheel must be removed first.
- The battery must be disconnected for at least 10 minutes.
Correct answer: The key must be turned to the 'ACC' or 'ON' position.
Most ignition lock cylinders are designed with a retaining pin or wafer that can only be accessed and depressed when the key is turned to the 'ACC' or 'ON' (RUN) position. This is a security feature to prevent the lock from being easily pulled out by thieves. [1, 2, 15]
Question 3: A locksmith is rekeying an ignition cylinder to match a customer's existing door key. After inserting the new wafers and the key, several wafers do not sit flush with the cylinder body. Which of the following is the most appropriate next step?
- Force the cylinder into the housing, as it will wear in over time.
- File down the protruding wafers until they are perfectly flush.
- Lubricate the cylinder heavily to allow the wafers to retract.
- Verify the wafer numbers and their positions according to the key cuts. (Correct answer)
Correct answer: Verify the wafer numbers and their positions according to the key cuts.
For a lock cylinder to function, all wafers or tumblers must be perfectly flush with the plug when the correct key is inserted. Wafers that protrude indicate that either the wrong wafer depth was used in a specific position or the sequence is incorrect. The correct procedure is to remove the wafers and re-evaluate the key cuts to ensure the correct wafers are in the correct positions. [12, 22, 28]
Question 4: A GM vehicle with a VATS (Vehicle Anti-Theft System) cranks but will not start, and the security light is on solid. The locksmith has verified the key's resistor pellet is correct. What is the most likely electrical point of failure?
- A faulty fuel injector relay.
- Broken wires leading from the ignition lock cylinder. (Correct answer)
- A drained vehicle battery.
- The key's transponder chip has failed.
Correct answer: Broken wires leading from the ignition lock cylinder.
The GM VATS system reads the key's resistor pellet via a set of contacts inside the ignition lock cylinder. These contacts are connected by very thin wires that run down the steering column. Due to the constant rotation of the ignition, these wires are a common failure point, leading to an open or intermittent circuit. This causes the VATS module to receive an incorrect resistance reading, triggering the security light and a no-start condition. [11, 17]
Question 5: What is the primary purpose of a 'sidebar' in a high-security ignition lock cylinder?
- To complete an electrical circuit for the transponder antenna.
- To physically block the wrong key blank from being fully inserted.
- To act as a secondary locking mechanism that requires correct tumbler alignment before it will retract. (Correct answer)
- To provide a channel for lubrication to reach the internal components.
Correct answer: To act as a secondary locking mechanism that requires correct tumbler alignment before it will retract.
A sidebar is an advanced security feature that acts as a secondary locking mechanism. It is a bar that rests between the cylinder plug and the housing. Only when all tumblers (pins or wafers) are lifted to the correct height and, in some cases, rotated to the correct angle, will gates on the tumblers align to allow the sidebar to retract into the plug, permitting rotation. This adds significant pick resistance. [9, 10, 20]
Question 6: When replacing a faulty ignition switch that is electrically separate from the lock cylinder, which of the following is a critical step to ensure proper vehicle operation after installation?
- Ensuring the new switch is mechanically aligned with the actuator from the lock cylinder. (Correct answer)
- Programming the new switch to the vehicle's Body Control Module (BCM).
- Cutting a new key to match the electrical profile of the new switch.
- Waiting for a 10-minute security relearn period before reconnecting the battery.
Correct answer: Ensuring the new switch is mechanically aligned with the actuator from the lock cylinder.
The ignition switch is operated mechanically by an actuator rod or gear connected to the lock cylinder. It is critical that the mechanical position of the new switch (e.g., OFF, ACC, ON, START) perfectly matches the rotational position of the key cylinder. Misalignment can result in accessories not working, the vehicle not starting, or the starter not disengaging. [16, 30]
A customer's key turns freely in the ignition of an older Ford vehicle but does not engage the starter or power any accessories.
The key feels 'loose' with no distinct detents.
What is the most likely component that has failed?