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Test No. 14: All Functions Of Keyless Entry System Does Not Operate

  1. Lithium battery should be changed in the keyless entry remote transmitter. Using your finger, slide cover on remote transmitter slightly outward so clearance exist and then use screwdriver to carefully pry cover from remote transmitter. See Figure. DO NOT use excessive force when prying cover from remote transmitter.
  2. Note direction of battery installation. Using small screwdriver, remove battery from remote transmitter. See Figure. DO NOT use excessive force when prying battery from remote transmitter. DO NOT push on electrical terminals with your fingers. Install NEW battery in remote transmitter. Use care not to damage electrical terminals. Reinstall cover.
  3. Recheck keyless entry system operation. If keyless entry system still does not operate, go to next step. If keyless entry system operates, problem was defective battery in remote transmitter.
  4. Check multiplex control system to see if Diagnostic Trouble Code (DTC) B1242 (Toyota hand-held tester) or DTC No. 42 (open door indicator light) exists. See MULTIPLEX CONTROL SYSTEMS - SEQUOIA article. If DTC B1242 (Toyota hand-held tester) or DTC No. 42 (open door indicator light) does not exist, go to next step. If DTC B1242 (Toyota hand-held tester) or DTC No. 42 (open door indicator light) exists, perform service procedure and recheck keyless entry system operation.
  5. Ensure ignition is off. Disconnect electrical connector at wireless door control receiver. Wireless door control receiver is located near center of instrument panel and contains a 5-pin electrical connector. See Figure. Note location of Body Electronic Control Unit (ECU). See Figure. Body ECU is located behind driver's side of instrument panel and contains 3 electrical connectors. Disconnect electrical connector B7 at body ECU. See Figure.
  6. Using ohmmeter, check for continuity between terminal No. 3 (Violet wire) at electrical connector for wireless door control receiver and terminal No. 10 (Violet wire) at electrical connector B7 for body ECU. For terminal identification on wireless door control receiver electrical connector, see Fig 1. For terminal identification on electrical connector B7 for body ECU, see Figure. If continuity exists, reinstall electrical connectors and go to next step. If continuity does not exist, repair wiring as necessary. Reinstall electrical connectors and recheck keyless entry system operation.
    Fig 1: Identifying Terminals On Wireless Door Control Receiver Electrical Connector
    G00023089Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  7. Replace wireless door control receiver with a known-good wireless door control receiver and recheck keyless entry system operation. If keyless entry system still does not operate, go to next step. If keyless entry system operates, original wireless door control receiver was defective.
  8. If Toyota hand-held tester is available, go to next step. If Toyota hand-held tester is not available, go to step  10.
  9. Connect hand-held tester to Data Link Connector (DLC) No. 3. See Figure. Using hand-held tester manufacturer's instructions, check operation of key unlock warning switch while using the DATA LIST. Key unlock warning switch should be on when ignition key is in ignition lock cylinder and should be off when ignition key is removed from ignition lock cylinder. If key unlock warning switch does not operate properly, remove hand-held tester. Go to next step. If key unlock warning switch operates properly, remove hand-held tester. Go to step  12.
  10. Check key unlock warning switch. See KEY UNLOCK WARNING SWITCH  under COMPONENT TESTS. If key unlock warning switch is okay, go to next step. If key unlock warning switch is defective, replace key unlock warning switch and recheck keyless entry system operation. See KEY UNLOCK WARNING SWITCH  under REMOVAL & INSTALLATION.
  11. Check key unlock warning switch circuit by checking Yellow/Green wire and electrical connectors between terminal No. 2 at key unlock warning switch and terminal No. 22 at body ECU electrical connector B7. See WIRING DIAGRAMS in POWER DOOR LOCKS & REMOTE KEYLESS ENTRY SYSTEMS - SEQUOIA article. Key unlock warning switch may also be referred to as unlock switch. For body ECU electrical connector terminal identification, see Figure. If wiring harness and electrical connectors are okay, go to next step. If wiring harness or electrical connector is defective, repair as necessary and recheck keyless entry system operation.
  12. Check body ECU for proper voltage and input signals. See BODY ELECTRONIC CONTROL UNIT  under PIN VOLTAGE TESTS. If proper voltage and input signals exist, go to next step. If proper voltage and input signals do not exist, repair as necessary and recheck keyless entry system operation.
  13. Replace body ECU with a known-good body ECU and recheck keyless entry system operation. If keyless entry system operates, original body ECU was defective. If keyless entry system still does not operate, check wiring harness and electrical connectors for body ECU for intermittent problem. See WIRING DIAGRAMS in POWER DOOR LOCKS & REMOTE KEYLESS ENTRY SYSTEMS - SEQUOIA article. Repair wiring harness or electrical connector as necessary.
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