Thinking about purchasing a new car? Use our new Car Loan Calculator to estimate your monthly car payment!

Chevrolet Lumina Passlock Bypass Instructions

by Mark Robinson

The Chevrolet Lumina comes equipped with Passlock, an anti-theft device that immobilizes a vehicle during theft attempts by disabling the ignition system. A special key with a resistor pellet mounted in the center is required to start the vehicle. The ignition cylinder matches the resistance of the pellet with the resistance required for the Passlock system to recognize the key. If the system can no longer recognize the resistor due to wear or age, the vehicle will not be able to start. The Passlock system can be bypassed, but an extensive amount of work is required to do so.

Pull the hood release lever on the left side of the driver's side foot well. Walk to the front of the Lumina and locate the metal hood release latch on the underside of the front of the hood. Pull the latch upward to open the hood. Use a combination wrench to disconnect the negative terminal cable from the battery.

Use the multimeter to measure the resistance of the pellet inside the ignition key. Set the multimeter to measure Ohms in the 20 k range. Place the probes on both sides of the pellet and record the measurement on the multimeter display.

Cut 16-gauge wiring into two 4-inch pieces. Strip 1/16-inch of insulation from each end of both wires.

Use a soldering iron to connect one or more resistors of the appropriate resistance to both wires. In order to match the resistance of the Passkey pellet, you may have to use more than one resistor. Solder each resistor in sequence, starting with the resistor with the highest resistance and ending with one of the lowest resistance. Solder the resistors to one end of each 4-inch piece of wire. Measure the soldered resistors from the wire ends with the multimeter and make sure the value displayed roughly matches the pellet resistance within a 2 percent margin of error.

Cut a length of heat-shrink tubing and cover the resistors and wires. Allow a small amount of tubing to hang over each end, as it will shrink to a smaller size once heat is applied. Shrink the tubing with a hair dryer. Use a crimping tool to crimp a male bullet connector on one end of the wire and a female bullet connector on the other end.

Remove the under-dash kick panel and locate the orange wire running along the length of the steering column. The wire will also have a rubbery covering. Do not cut or otherwise tamper with any yellow wire or any wires covered with yellow harness tape; otherwise, the air bag may be discharged.

Cut through the orange wire to expose the two white wires inside. Cut the white wires and strip 1/16-inch of insulation from both wires on the ends leading toward the engine. Crimp a male bullet connector to one wire and crimp a female connector on the other. Connect the wires with the resistors soldered together to the white wires using the bullet connectors.

Replace the under-dash kick panel and reconnect the negative terminal cable to the battery. Attempt to start the Lumina by inserting the key into the ignition cylinder and turning the cylinder to the "START" position. If the Lumina does not start, disconnect the battery and remove the kick panel once more. Remove insulation from the other end of the two white wires coming from the ignition cylinder and crimp a male and female bullet connector to each end. Remove the resistors from the opposite end of the white wires and reconnect the white wires to one another using the bullet connectors to restore Passlock functionality.

Warning

  • Always disconnect the battery to minimize the chance of shock and serious injury.

Items you will need

About the Author

Mark Robinson is a freelance graphic designer and writer. Since 2008 he has contributed to various online publications, specializing in topics concerning automotive repair, graphic design and computer technology. Robinson holds a Bachelor of Science in graphic design from Alabama A&M University.

More Articles

Photo Credits

  • Jupiterimages/Polka Dot/Getty Images