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Home >> Toyota >> 2004 >> Matrix Base, FWD, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 98 (Multiplex Control Systems) >> Diagnostic Tests >> DTC B1221/21: Driver Door Power Window Switch Circuit Malfunction >> 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.

Turn ignition on and retrieve DTCs. If DTC B1221/21 is present before operating any power window switch on driver door or if DTC B1221/21 is not present while operating any power window switch on driver door, test power window switch. Driver door ECU is also referred to as power window master switch. See DRIVER DOOR CONTROL SYSTEM under TROUBLE SHOOTING in BODY CONTROL SYSTEMS - AVALON article under COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT. If switch tests okay, check and repair wiring harness. See POWER WINDOWS in SYSTEM WIRING DIAGRAMS article. After repairs have been made, perform confirmation test. See CONFIRMATION TEST  under SELF-DIAGNOSTIC SYSTEM.