2005 Scion tC AutomaticFACTORY OEM SERVICE PROCEDURE

Inspection Procedure

  1. INSPECT FUSE (AM1, GAUGE, FL DOOR) 
    1. Remove the AM1, GAUGE and FL DOOR fuses from the instrument panel J/B.
    2. Measure the resistance of the fuses.
      1. Standard: Below 1 Ω 

    NG: REPLACE FUSE 

    OK: GO TO NEXT STEP 

  2. INSPECT RELAY (Marking: IG1) 
    1. Remove the IG1 relay from the instrument panel J/B.
    2. Measure the resistance of the relay.

      Standard: 

      IG1 RELAY TERMINAL RESISTANCE

      Tester Connection Specified Condition
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω
      (when battery voltage is applied to terminals 1 and 2)
      Fig 1: Inspecting Relay (Marking: IG1)
      G03065217Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE RELAY (IG1) 

    OK: GO TO NEXT STEP 

  3. CHECK WIRE HARNESS (POWER WINDOW REGULATOR MASTER SWITCH ASSY - BATTERY AND BODY GROUND) 
    1. Disconnect the P9 master switch connector.
    2. Measure the voltage and resistance of the wire harness side connector.

      Standard: 

      POWER WINDOW REGULATOR MASTER SWITCH ASSY TERMINAL VOLTAGE

      Tester Connection Condition Specified Condition
      P9-10 (B) - Body ground Always 10 to 14 V
      P9-20 (IG) - Body ground Ignition switch OFF -> ON 0 V -> 10 to 14 V
      P9-2 (GND) Body ground Always Below 1 Ω
      Fig 2: Measuring Voltage & Resistance Of Wire Harness Side Connector
      G03065218Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: REPLACE POWER WINDOW REGULATOR MASTER SWITCH ASSY 

Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

Shop Manual-Ready ToolsCompare Repair QuoteQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

Rather have a pro handle this?

A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.

Comes to youSame-day available12-month warranty
Get a Free Quote

No obligation. See pricing before you book.