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Basic Function Test

NOTE: Remote transmitter operating distance can be affected by orientation of transmitter, radio interference or weak transmitter battery.
  1. Using inside door lock switch, lock and unlock door locks 3 times. Stand about 3 feet from outside driver's door handle and point remote transmitter toward vehicle. Depress any remote transmitter button for about one second. If doors lock and unlock, keyless entry system is okay. If doors do not lock and unlock, go to next step.
  2. Replace remote transmitter battery and repeat step  1. If keyless entry system does not operate, go to next step. If keyless entry system operates, system is okay.
  3. Perform self-diagnostic test. See SELF-DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If taillights do not flash as specified, go to next step. If taillights flash as specified, go to step  8.
  4. Repeat step  3 to verify method used to enter into SELF-DIAGNOSTIC mode. If taillights do not go on, check operation of taillights. See EXTERIOR LIGHTS article. If taillight operation is okay, go to next step.
  5. Insert key into ignition lock cylinder. Check continuity between ground and terminal No. 2 (Yellow/Red wire) of body ECU 23-pin harness connector B16. See Fig 1. If continuity exists, unlock warning switch circuit is okay, if continuity does not exist, go to next step.
  6. Check continuity of Yellow/Red wire between terminal No. 2 of body ECU 23-pin harness connector B16 and terminal No. 2 of unlock warning switch harness connector. If continuity is not present, repair open in Yellow/Red wire. If continuity is present, go to next step.
  7. Check continuity between ground and terminal No. 1 (White/Black wire) of unlock warning switch. If continuity is not present, repair open in White/Black wire between unlock warning switch and ground behind left side of dashboard. If continuity is present, check unlock warning switch. See KEY UNLOCK WARNING SWITCH  under COMPONENT TESTS. Replace as necessary. See WIRING DIAGRAMS .
  8. Perform self-diagnostic test. See SELF-DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If system responds as specified, go to next step. If system does not respond as specified, go to step  10.
  9. Depress and hold any button on remote transmitter for 20 seconds and walk around vehicle. Release and depress button again. Ensure range is a minimum of 3 feet from vehicle. If remote transmitter operates 3 feet from vehicle, remote transmitter and receiver are operating correctly. If any functions are not operating, problem is with associated control module. See appropriate BODY CONTROL MODULES article. If remote transmitter does not operate 3 feet from vehicle, check range with another remote transmitter. If second remote transmitter does not operate 3 feet from vehicle, replace back door ECU. If second remote transmitter operates 3 feet from vehicle, replace faulty remote transmitter. See BACK DOOR ECU  under REMOVAL & INSTALLATION.
  10. Depress each button of two remote transmitters registered for this vehicle. If vehicle responds correctly from only one of the remote transmitters, replace faulty remote transmitter. If vehicle does not respond correctly from either remote transmitter, go to next step.
  11. Measure voltage between ground and terminal No. 2 (Blue/Red wire) at back door ECU harness connector. If battery voltage is present, go to next step. If battery voltage is not present, check engine compartment fuse MPX-B (15-amp). Replace MPX-B fuse if blown. If fuse is okay, check power distribution to fuse MPX-B, If power is present, repair open in Blue/Red wire between terminal No. 2 at MPX-B fuse and terminal No. 2 at back door ECU harness connector. See WIRING DIAGRAMS 
  12. Check continuity between ground and terminal No. 26 (White/Black wire) of back door ECU harness connector. See Fig 2. If continuity is present, replace back door ECU. See BACK DOOR ECU  under REMOVAL & INSTALLATION. If continuity is not present, repair open in White/Black wire between terminal No. 26 of back door ECU harness connector and ground at left rear quarter panel.
    Fig 1: Identifying Body ECU Harness Connector B16 Terminals
    G00020343Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 2: Identifying Back Door ECU Harness Connector Terminals
    G00020344Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002