When a key is inserted in the ignition, contacts that are
located in the steering column (ignition) lock cylinder contact a resistor
   pellet located in the ignition key. The theft deterrent   module measures
 the resistance of the key pellet. The module compares this   value to a value
 stored in memory. The theft deterrent  module  then performs one of the following
 functions:
|     •  | If the values match, the theft deterrent module performs the following
system enable functions: | 
 
|       •  | The module provides a ground for the theft deterrent relay at
terminal A4 (CKT 625, YEL/BLK). The ground enables the starter
 to operate. | 
 
|       •  | The module sends a proper pulse width modulated (PWM) signal to
the PCM. The signal travels via CKT 229 (DK BLU), terminal A3.
   When the PCM receives this input, the PCM enables the fuel delivery system. | 
 
|     •  | If the values do not match, the theft deterrent module performs
the following system disable functions for approximately 3 minutes: | 
 
|       •  | No ground is provided to the theft deterrent relay. The starter
is disabled. | 
 
|       •  | No command is given to the PCM in order to enable the fuel delivery
system. | 
 
If you turn the ignition switch to the RUN position anytime during the
system disable interval, the theft deterrent module disregards   the key pellet
 value until the 3 minute system disable interval is  complete.  This
 action occurs even if you use the correct key pellet value.
After approximately 3 minutes, the theft deterrent module performs
the following actions:
|     •  | The module measures the key pellet resistance. | 
 
|     •  | The module compares the key pellet resistance to a value stored
in memory. | 
 
If the values match, the theft deterrent module performs the system
enable function. If the values do not match, the module performs   the system
 disable functions again.
If the theft deterrent module is unable to measure the key pellet resistance
due to a damaged or a missing pellet, the module  does  not perform the system
 enable or system disable functions. No 3 minute   interval is performed.
 A measurable key with the correct resistance value   can be used in order
 to start the vehicle.
Security Indicator Operation
When you turn the ignition switch to the RUN position, the SECURITY
indicator illuminates for approximately 5 seconds. The indicator notifies
   the driver that the system operates correctly.
The theft deterrent system indicator operates in the following 4 modes:
|     •  | The indicator illuminates when you turn the ignition switch to
RUN (5 second bulb check). This condition shows that the indicator
  and the system operate  correctly. | 
 
|     •  | The indicator illuminates after the engine starts. This condition
indicates that one of the following conditions has occurred: | 
 
|        -  | The theft deterrent module is not properly programmed. You may
use more than one key code value in order to start the vehicle. The   improperly
 programmed module condition usually occurs on a vehicle where  the  module
 has been recently replaced. | 
 
|        -  | The theft deterrent module detected a malfunction in the PASS-Key®
II system while the engine was running. Verify that the   following conditions
 are met. For further diagnosis, refer to 
Vehicle Theft Deterrent (VTD) System Check 
. | 
 
|    •  | The theft deterrent module connections are secure. | 
 
|    •  | You are using a good ignition key. | 
 
|     •  | The indicator illuminates, but the engine does not start. The
theft deterrent module has detected an incorrect key pellet   resistance key
 code value. The system disable functions activate. Perform  the following
 steps: | 
 
|         1.  | Remove the key from the ignition. | 
 
|         2.  | Verify that the correct key code (key pellet) is being used in
order to start the vehicle. Use a J 35628-A 
 interrogator in order to measure each key pellet for the
  vehicle.  All key codes should match. | 
 
|         3.  | Wait for approximately 3 minutes for the system disable
timer to expire. Use a known good key with the correct key code in order to
  attempt  to restart the engine. | 
 
|     •  | The indicator flashes and the engine does not start. The theft
deterrent module has detected an open or short in the ignition key   resistor
 input circuit. During this mode of operation, the theft deterrent module
does  not start the system disable timer. Refer  to 
Vehicle Theft Deterrent (VTD) System Check 
. |