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Keypad Input

  1. Disconnect control module connector C406 and keypad connector. Check for short to ground between pin Nos. 3 through 7 of connector C406. See Figure and Figure . If reading of 100,000 ohms or less indicates a short. Is there a short to ground? If no, go to next step. If yes, go to step  3 . Repeat Quick Test  .
  2. Disconnect C406 module connector. Check for short between button failing and (Brown) wire. Is there a short to Circuit? If no, go to step  4 . If yes, replace keypad. Repeat Quick Test  . See WIRING DIAGRAMS  .
  3. Remove door trim panel. See POWER DOOR LOCKS, FUEL DOOR RELEASE & TRUNK RELEASE for trim panel removal. Disconnect keypad connector. Check for short between connector and ground. If no low resistance to ground, service harness between module connector and keypad connector. Repeat Quick Test  . If low resistance to ground, replace switch. See WIRING DIAGRAMS  .
  4. Verify Circuit 124 is not shorted to ground or open from pin No. 3 to pin No. 12 of connector C406 with 1/2 button depressed. See WIRING DIAGRAMS  . Is there a short to ground or open? If no continuity exists, go to next step. If continuity exists, repair open or short in (Brown) wire. Repeat Quick Test  .
  5. With control module connector connected to control module, connect voltmeter between terminal No. 1 of connector C406 and ground. For each button that fails to light keypad, momentarily connect jumper between terminal No. 12 of connector C406 and terminals No. 1, 2, 4, 5, 6 and 8. Wait 5 seconds between jumper connections. If reading is 5 volts or more for 5 seconds during each test, go to next step. If reading is less than 5 volts 5 seconds during each test, replace control module. Repeat Quick Test  .
  6. Disconnect keypad connector. Check for continuity between terminal No. 5 and every pin on keypad. See Figure . Then check between terminal No. 4 and every terminal on the keypad until every terminal pair has been checked. If all circuits are open except between terminals No. 1 and 8, go to next step. If a short is found, replace keypad. Repeat Quick Test  .
  7. Check for continuity between terminal No. 7 and No. 5 of keypad connector. Repeat for each key in turn, checking continuity between the corresponding terminal, and terminal No. 7 of keypad connector. Is there continuity? If yes, service open or short in circuit of non-functional buttons. Repeat Quick Test  . If no, replace keypad. Repeat Quick Test  .
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