Replacing the key tumbler or lock cylinder on your Chevy truck can be a simple process on vehicles that have few components. However, it can be an involved and potentially dangerous job on vehicles equipped with air bag systems, as working near impact sensors may expose you to a serious accident if you fail to proceed properly. Still, in and of itself, the job of installing a new key lock cylinder is not difficult and you can do it at home with the use of a few common tools.
If your Chevy pickup truck comes equipped with an Air Bag system, you need to disable it. This will prevent you from accidentally hitting an impact sensor and deploying the air bags. First, set the front wheels to point straight ahead and turn the ignition key to the Lock position. Disconnect the black ground battery cable and remove all the air bag fuses.
Now look for the yellow two-way connector at the base of the steering column. You might need to remove the knee bolster for access. This connector has a small plastic pin at the side that you need to remove first before you can unplug the connector. If your truck has a passenger air bag, unplug the yellow connector located behind the glove box as well. You air bag system is now disarmed.
Make sure the ground battery cable is disconnected and the front wheels are pointing straight ahead. The steering wheel on your Chevy pickup may have a simple horn cap with an electrical connector underneath or an air bag module cover.
Covers on steering wheel models without air bags pop out loose using an appropriate prying tool or by unscrewing the retaining screws from the underside of the wheel. On models with air bags, you need a small prying or awl tool to release the cover spring retainers through the holes located on the underside of the steering wheel.
With the cover out of the way, you can proceed to remove the snap ring and retaining nut from the steering column shaft. Just make sure not to hit the steering column as you work on it. On many Chevy models, the steering column collapses on impact to prevent driver injuries during an accident.
Before you remove the steering wheel, make match marks on the steering wheel and column shaft so that you replace it in the same position. Then use a steering wheel puller to detach it from the steering column.
On some Chevy pickup models, you can reach the ignition lock cylinder by simply unfastening the turn signal without unplugging it and removing the buzzer switch assembly. However, make sure to use a screwdriver with a strong magnetic tip to unfasten the mounting screw from the lock cylinder. If you drop this screw into the steering column, you might have to disassemble it to recover the screw.
On most recent models, you need to detach the steering column from the instrument panel first, in order to reach ignition lock cylinder. With the steering column free from the instrument panel, remove the upper and lower steering column mounting screws. Then detach the lower cover only.
To gain access to the lock cylinder, lift the upper steering column cover slightly, just enough to give you access to the lock cylinder underneath. Turn the ignition key to the Start position and, using a 1/16-inch hex wrench, push down on the cylinder retaining pin through the hole on the upper side of the cylinder. Then turn the key to the Run position and remove the key lock cylinder from the steering column.
When installing the lock cylinder on these models, set the cylinder to the Run position and push the cylinder into the lock module. Then reassemble the rest of the components in the reverser order of removal.
To arm the bag system on your Chevy, connect the yellow two-way connectors on the passenger's and driver's side and reinstall all the air bag fuses. Then connect the ground battery cable.
Sit in the passenger's side of your pickup and turn the ignition key to the Run position. Make sure the air bag warning light on the instrument panel flashes seven times. This means your bag system is armed. If not, make sure everything is properly connected and check for Diagnostic Troubleshooting Codes (DTCs) that might have been set as you disarmed the system. You can erase these trouble codes using a scan tool.
