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Keypad Illumination

  1. Disconnect connectors C418 and C406 from control module. Measure voltage between terminal No. 13 of connector C406 and ground. Measure voltage between terminals No. 13 and 14 of connector C418 and ground. If reading is 10 volts or greater, go to next step. If reading is less than 10 volts, check and replace fuse as necessary. If fuse is okay, repair open or short in Light Green/Yellow wire or Black/White wire. See WIRING DIAGRAMS  . Repeat Quick Test  .
  2. Disconnect connectors C418 and C406 from control module. Measure voltage between terminal No. 2 of connector C406 and ground. Measure voltage between terminals No. 5 and 6 of connector C418 and ground. See Figure and Figure . If continuity exists, go to next step. If no continuity exists, service open in affected circuit. Repeat Quick Test  .
  3. Disconnect keypad connector and control module connector C406. Check for continuity between terminal No. 1 of connector and ground. If no continuity, go to next step. If continuity to ground, service short in (Light/Blue) wire. Repeat Quick Test  . See WIRING DIAGRAMS  .
  4. Reconnect keypad connector. Leave connector C406 disconnected. Check resistance between terminal No. 1 of the C406 connector and ground. Is resistance greater than 10 ohms? If no, refer to PINPOINT TEST D  . If yes, go to next step.
  5. Disconnect the keypad connector. Check resistance between terminals No. 3 and 7 of the keypad connector in driver's door. See Figure and Figure . Is resistance greater than 10 ohms? If yes, replace keypad. Repeat Quick Test  . If no, go to next step.
  6. Disconnect keypad connector and control module connector C406. Check for continuity between terminal No. 1 of control module connector and terminal No. 7 of keypad connector. If continuity exists, go to next step. If no continuity exists, service open in (Light/Blue) wire. See WIRING DIAGRAMS  .
  7. Disconnect keypad connector. Check for continuity between terminal No. 8 and ground. If continuity exists, go to next step. If no continuity exists, repair open in keypad ground (Black) wire. Repeat Quick Test  . See WIRING DIAGRAMS  .
  8. Check for a short between terminal No. 12 of control module connector C406 and ground. Is there a short? If no short exists, go to next step. If continuity exists, service short in (Brown) wire. Repeat Quick Test  . See WIRING DIAGRAMS  .
  9. Disconnect connector C406 and keypad connector. Check for continuity between terminal No. 12 of connector C406 and terminal No. 7 of keypad connector. Is there continuity? If yes, replace keyless entry module. If no, service (Brown) wire. Repeat Quick Test  . See WIRING DIAGRAMS  .
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