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Test No. 4: Communication Circuit

  1. Disconnect tilt/telescopic ECU connectors. Connect jumper wire between DLC2 terminal E1 and terminal Tc. See Figure. Turn ignition on. Check open door indicator light for any trouble codes. If Codes 14 and 15 are present, go to next step. If no codes are present, check tilt/telescopic ECU. See STEERING COLUMN - POWER TILT SYSTEM article.
  2. Disconnect driver's door ECU connectors. Connect jumper wire between DLC2 terminal E1 and terminal Tc. See Figure. Turn ignition on. Check open door indicator light for any trouble codes. If Codes 14 and 15 are present, go to next step. If no codes are present, check driver's door ECU. See DRIVER'S DOOR ECU  under PIN VOLTAGE TESTS.
  3. Disconnect front passenger's door ECU connectors. Connect jumper wire between DLC2 terminal E1 and terminal Tc. See Figure. Turn ignition on. Check open door indicator light for any trouble codes. If Codes 14 and 15 are present, go to next step. If no codes are present, check front passenger's door ECU. See FRONT PASSENGER'S DOOR ECU  under PIN VOLTAGE TESTS.
  4. Disconnect driver's door and front passenger's door ECU connectors. Connect jumper wire between DLC2 terminal E1 and terminal Tc. See Figure. Turn ignition on. Check open door indicator light for any trouble codes. If Codes 14 and 15 are present, repair or replace wiring harness between driver's door ECU, body ECU and front passenger's door ECU. If no codes are present, repair or replace wiring harness between driver's door ECU, tilt/telescopic ECU and front passenger's door ECU.
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