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Test E: Doors Do Not Unlock Using Keypad

  1. Turn ignition off. Connect NGS tester following manufacturer's instructions. Turn ignition switch to RUN position. Monitor RAP PID KEY_PAD while pressing each number on keyless entry keypad. If more than one number is displayed with any single button, replace keypad. If no numbers are displayed, go to next step.
  2. Monitor RAP PID KEY_PAD while pressing each number on keypad individually. If 1/2, 3/4, 5/6, 7/8 and 9/0 are displayed, go to next step. If more than one number but not all numbers are displayed, replace keypad. Recheck system operation. If all numbers do not display, go to step  8 . If a single number fails to display, go to step  7 .
  3. Turn ignition off. Disconnect RAP module 22-pin connector C257. Measure voltage between ground and RAP module connector C257 terminal No. 22 (Pink/Yellow wire). If more than 10 volts exists, go to next step. If 10 volts or less exists, repair open in Pink/Yellow wire. Recheck system operation.
  4. Measure voltage between ground and RAP module connector C257 terminal No. 11 (Pink/Light Green wire). If more than 10 volts exists, replace RAP module. Recheck system operation. If 10 volts or less exists, repair open in Pink/Light Green wire. Recheck system operation.
  5. Disconnect keypad switch 8-pin connector C514. Using NGS tester, monitor RAP PID KEY_PAD. If any numbers are displayed, go to next step. If no numbers are displayed, replace keyless entry keypad. Recheck system operation.
  6. Disconnect RAP module 22-pin connector C257. Measure resistance between ground and keypad connector terminals No. 1 (Red wire), No. 3 (Light Blue/Yellow wire), No. 4 (Light Green/Red wire), No. 5 (Yellow/Black wire) and No. 6 (Yellow wire) individually. If resistance is greater than 10 k/ohms at all terminals, replace RAP module. Recheck system operation. If resistance is 10 k/ohms or less at any terminal, repair short to ground in appropriate circuit. Recheck system operation.
  7. Turn ignition off. Disconnect RAP module 22-pin connector C257. Disconnect keyless entry keypad 8-pin connector C514. Measure resistance of individual circuits between RAP module connector C257 and keypad connector C514 as specified. See KEYPAD CIRCUIT RESISTANCE  table. If all resistances are 5 ohms or less, go to next step. If any resistances are greater than 5 ohms, repair open in appropriate wire. Recheck system operation.
    KEYPAD CIRCUIT RESISTANCE

    Keypad Connector Terminal No. Wire Color RAP Module Connector Terminal No.
    1 Red 8
    3 Light Blue/Yellow 5
    4 Light Green/Yellow 6
    5 Yellow/Black 19
    6 Yellow 7
  8. Measure resistance between keyless entry keypad connector terminal No. 8 (Brown wire) and keyless entry keypad connector terminals No. 1 (Red wire), No. 3 (Light Blue/Yellow wire), No. 4 (Light Green/Red wire), No. 5 (Yellow/Black wire) and No. 6 (Yellow wire) individually. If all resistances are less than 5 ohms, replace keyless entry keypad. Recheck system operation. If resistance is 5 ohms or greater at any terminal, repair open in appropriate wire. Recheck system operation.
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