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Test C: Locks Inoperative From Keypad

NOTE: Ensure all door locks operate properly from door lock switches before proceeding with this test.
  1. Turn ignition switch to LOCK position. Connect New Generation Star (NGS) tester to data link connector. Monitor PID KEYPAD for RAP module. If no numbers are displayed, go to next step. If more than one number is displayed, replace keypad assembly. If one number is displayed, go to step 5).
  2. Monitor PID KEYPAD on NGS tester. Press each number on keypad one at a time. If all numbers entered on keypad are displayed on NGS display, go to next step. If no numbers entered on keypad are displayed on NGS display, go to step 8). If all but one number entered on keypad is displayed on NGS display, go to step 7). If one or more but less than 4 numbers entered on keypad are displayed on NGS display, replace keypad.
  3. Disconnect RAP module harness connector C254. Measure voltage at terminal No. 22 (Pink/Yellow wire) at RAP module harness connector C254. See Figure . If battery voltage exists, go to next step. If battery voltage does not exist, repair open in Pink/Yellow wire.
  4. Measure voltage at terminal No. 11 (Pink/Light Green wire) at RAP module harness connector C254. If battery voltage exists, replace RAP module. If battery voltage does not exist, repair open in Pink/Light Green wire.
  5. Turn ignition switch to LOCK position. Disconnect keypad harness connector. Monitor PID KEYPAD on NGS tester. If any numbers are still displayed, go to next step. If no number are displayed, replace keypad.
  6. Turn ignition switch to LOCK position. Disconnect RAP module harness connector C253. Measure resistance between ground and all wire at keypad harness connector except Black wire and Light Blue wire. If all resistance reading are greater than 10,000 ohms, replace RAP module. If any resistance reading is 10,000 ohms or less, repair short to ground in appropriate wire.
  7. Turn ignition switch to LOCK position. Disconnect RAP module harness connector C253. See Figure . Disconnect keypad harness connector. Measure resistance in wires between keypad harness connector and RAP module harness connector C253. See WIRING DIAGRAMS  . If all resistance reading are 5 ohms or less, replace keypad. If any resistance reading is greater than 5 ohms, repair open in appropriate wire.
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