How to Reset a 98 Chevy Suburban Security Light

by Blaze Johnson Google

    The Chevrolet Suburban has a long and rich history, dating all the way back to the 1935 heavy duty, two-door Suburban Carryall. Although styling kept up with the times during its first 38 years of production, the mighty truck-like wagon didn't receive many passenger or “family friendly” enhancements until the early and mid-1970s. Your 1998 Suburban received a few new bells and whistles that didn't exist in prior-year models, such as an optional OnStar system, Autotrac four-wheel drive and the Passlock theft deterrent system. After replacing the Passlock module or ignition sensor, or when installing a used powertrain control module, it will be necessary to perform a relearn procedure to turn off the “Security” warning light and enable the fuel system.

    Items you will need

    • Automotive trickle charger
    Step 1

    Open the hood and connect a trickle charger to the battery, according to the product's instructions. Although not absolutely necessary if your vehicle has a strong and fully charged battery, connecting a trickle charger will help avoid draining the battery during the 30-minute relearn procedure.

    Step 2

    Switch the ignition to the third, or “Run” position. Turn off all accessories, such as the radio, interior lights and climate control. Turn the ignition to the fourth, or “Start” position – momentarily – to crank the engine, then release the ignition to the “Run” position. Wait approximately 10 minutes, until the “Security” light goes out, then switch off the ignition and wait 10 seconds.

    Step 3

    After switching off the ignition and waiting 10 seconds, repeat Step 2 two more times. After waiting 10 seconds on the last cycle, start the engine to complete the relearn procedure. Turn off the engine and disconnect the trickle charger, if necessary.


    • Performing the relearn procedure may also serve as a temporary means to start the vehicle if there's an issue with the Passlock sensor providing an out-of-spec resistance value to the Passlock EVO module.