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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 B1251/51: Power Mirror 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.
  1. Ensure engine starts normally. Repair as required. Test power mirror switch. See POWER MIRROR SWITCH under COMPONENT TESTS under POWER MIRRORS - AVALON article under MIRRORS in ACCESSORIES & EQUIPMENT. If power mirror switch is not okay, replace switch. If power mirror switch is okay, go to next step.
  2. Turn ignition off. Disconnect power seat ECU 25-pin electrical harness connector P21. See Figure. Remove and disconnect Black power mirror switch 10-pin electrical harness connector R5. See Fig 1. Check and repair connectors and circuits between power seat ECU and power mirror switch. See MEMORY SYSTEMS in SYSTEM WIRING DIAGRAMS article.
  3. After repairs have been made, perform confirmation test. See CONFIRMATION TEST  under SELF-DIAGNOSTIC SYSTEM.
Fig 1: Identifying Black Power Mirror Switch Electrical Harness Connector R5 Terminals
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