Ignition Key Transponder Value

The ignition key transponder value is used to determine if the correct key is being used to start the vehicle. The ignition key transponder value is read when the ignition is first turned on. If the ignition key transponder value matches the value stored in the PASS-Key (R) III module, the PASS-Key (R) III module sends the fuel continue password to the Powertrain Control Module (PCM) allowing the vehicle to start. If the ignition key transponder value does not match the value stored in the PASS-Key (R) III module, the PASS-Key (R) III module sends the fuel disable password to the PCM preventing the vehicle from starting.

While the vehicle is running, the ignition key transponder value is also read. If the PASS-Key (R) III module reads an open, short, or incorrect transponder value for 30 consecutive seconds. The "Security" indicator illuminates until the module verifies the fault is corrected. The "Security" indicator will illuminate for the first 30 seconds of each ignition cycle if a fault is detected. The PASS-Key (R) III module allows the vehicle to start during this condition.

When diagnosing the system you must leave the ignition on for at least 30 seconds to verify problem.