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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 between ground and 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 between terminal No. 22 at RAP module harness connector C254, splice S201 (located at left kick panel) and terminal No. 85 at all door lock relay harness connector C255.
  4. Measure voltage between ground and 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 between terminal No. 11 at RAP module harness connector C254, splice S200 (located at left kick panel) and terminal No. 85 at all door unlock relay harness connector C256.
  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 wires except Black wire and Light Blue wire at keypad harness connector C500. If all resistance readings are greater than 10/k ohms, replace RAP module. If any resistance reading is 10/k ohms or less, repair short to ground in appropriate wire between keypad harness connector C500 and RAP module harness connector C253.
  7. Turn ignition switch to LOCK position. Disconnect RAP module harness connector C253. See Figure . Disconnect keypad harness connector C500. Measure resistance in wires between keypad harness connector and RAP module harness connector C253. See WIRING DIAGRAMS  . If all resistance readings are 5 ohms or less, replace keypad. If any resistance reading is greater than 5 ohms, repair open in appropriate wire between keypad harness connector C500 and RAP module harness connector C253.
  8. Press keypad number while measuring resistance between keyless entry key pad connector C500F (female) terminal F8 (Brown wire) and the following: terminal F3 (Button 1/2, Light Blue/Yellow wire), terminal F4 (Button 3/4, Light Green/Red wire), terminal F5 (Button 5/6, Yellow/Black wire), terminal F6 (Button 7/8, Yellow wire) and terminal F1 (Button 9/0, Red wire). If resistance is less than 5 ohms, then circuit is okay, reassemble and retest. If resistance is more than 5 ohms, then replace keypad switch assembly and retest system. See WIRING DIAGRAMS  .
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