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System Operation Check

NOTE: The following test verifies that wireless door lock ECU receives and recognizes signals from remote transmitter. Perform this test when remote transmitter does not operate properly. If remote transmitter operates properly and problems still exist, diagnose by symptom. See SYMPTOM DIAGNOSIS .
  1. Remove key from ignition switch. Close and lock all doors. While standing outside vehicle near driver's door, point transmitter toward vehicle. Press door LOCK, and then UNLOCK button on transmitter for about one second. If doors do not lock and unlock properly, go to next step. If doors lock and unlock properly, system is okay at this time.
  2. Check transmitter battery voltage (3 volts) or replace battery and recheck door lock operation using transmitter. If door locks still do not operate, go to next step.
  3. Remove key from ignition switch. Close and lock all doors. Perform the following within 35 seconds: insert key into ignition switch, and then remove it. Insert key once more. Turn ignition on, and then off one time within 5 seconds. Within 30 seconds, turn ignition on and off 9 additional times. Buzzer should sound a short tone followed by a longer tone; and taillights should flash, indicating successful entry to diagnostic mode. If buzzer and taillights operate as specified, go to next step. If buzzer and taillights do not operate as specified, go to step  7.
  4. Press LOCK button on transmitter. Buzzer and taillights should output (.2 second) once about every .5 second. Press UNLOCK button on transmitter. Buzzer and taillights should output 2 times about every .5 second. Press PANIC button on transmitter. Buzzer and taillights should output (.6 second) about every .5 second. If buzzer and taillights operate as specified, go to next step. If buzzer and taillights do not operate for each button pressed, go to step  8. If buzzer and taillights output for an extended amount of time, go to step  9.
  5. Standing at least 3 feet from vehicle, press and hold any transmitter button. After holding button for 20 seconds, buzzer should stop. If operation is not as specified, go to next step. If operation is as specified, go to step  10.
  6. Repeat procedure in step  5 using a known-good transmitter and check effective range. If buzzer and taillights operate as specified, replace original transmitter. If buzzer and taillights do not operate properly using either transmitter, wireless door lock ECU is faulty.
  7. Ensure step  3 was performed correctly. Repeat if necessary, and then go to step  4. If step  3 was performed correctly, but taillights do not flash, check taillight system. See wiring diagrams in EXTERIOR LIGHTS article. Repair as necessary. If taillights flash, but diagnostic mode cannot be entered, go to step  11.
  8. Transmitter or wireless door lock ECU is faulty. Use a known-good transmitter to re-enter diagnostic mode. If operation is okay, replace original transmitter. If operation is not okay, wireless door lock ECU is faulty.
  9. A long continuous output of buzzer and/or taillights indicates transmitter is operating, but transmitter code is not recognized by ECU. Program transmitter. See PROGRAMMING . Recheck remote door lock operation. If transmitter cannot be programed, go to next step.
  10. Check wireless door lock ECU circuit. See WIRELESS DOOR LOCK ECU CIRCUIT  under CIRCUIT TESTS. Replace ECU if necessary. If ECU is okay, check and repair system wire harness. See WIRING DIAGRAMS .
  11. Using DVOM, check for continuity between ground and terminal No. 10 (Red/Black wire) at wireless door lock ECU harness connector. Continuity should be present with key inserted into ignition key cylinder, and not present with key removed. If continuity is as specified, check wireless door lock ECU. See WIRELESS DOOR LOCK ECU CIRCUIT  under CIRCUIT TESTS. If continuity is not as specified, check key unlock warning switch. See WIRING DIAGRAMS . Repair as necessary.
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