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Home >> Toyota >> 2003 >> Matrix Base, FWD, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 79 (Multiplex Control Systems) >> Diagnostic Tests >> DTC B1212/12: Front Passenger Door Ecu Communication Stopped >> Diagnostic Procedure
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Diagnostic Procedure

WARNING: This page is about a different car, the 2002 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn ignition on. Operate power window switch on front passenger door. If power window operates, go to next step. If power window does not operate, diagnose front passenger door ECU and retest system. See FRONT PASSENGER DOOR CONTROL SYSTEM under TROUBLE SHOOTING under BODY CONTROL SYSTEMS - AVALON article under COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT.
  2. Turn ignition off. Disconnect front passenger door ECU 20-pin electrical harness connector F14 and body control ECU 25-pin electrical harness connector B5. See Figure. Using DVOM, check continuity of Green/Black wire between front passenger door ECU 20-pin electrical harness connector F14 terminal No. 10 and body control ECU 25-pin electrical harness connector B5 terminal No. 21. If continuity exists, diagnose front passenger door ECU and retest system. See FRONT PASSENGER DOOR CONTROL SYSTEM under TROUBLE SHOOTING under BODY CONTROL SYSTEMS - AVALON article under COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT. If continuity does not exist, repair open circuit in Green/Black wire between body control ECU and front passenger door ECU and retest system. See COMPUTER DATA LINES in SYSTEM WIRING DIAGRAMS article.
  3. After repairs have been made, perform confirmation test. See CONFIRMATION TEST  under SELF-DIAGNOSTIC SYSTEM.
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