Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Inspection Procedure
- CHECK FOR DTC
- Operate the driver door power window. Check if any DTC is output.
Result
RESULT REFERENCE CHARTResult Proceed to No DTC is output A DTC is output B
B: GO TO DTC CHART
A: Go to Next Step
- Operate the driver door power window. Check if any DTC is output.
- READ VALUE OF TECHSTREAM (POWER WINDOW SWITCH)
- Check the Data List for proper functioning of the power window switch.
Multiplex network door ECU front LH (driver door ECU)
ITEM MEASUREMENT NORMAL CONDITION CHARTItem Measurement Item / Display (Range) Normal Condition Diagnostic Note P/W AUTO SW Driver door power window AUTO switch ON / OFF ON: Driver door power window
AUTO switch operates
OFF: Driver door power window
AUTO switch does not operate- OK: ON (switch is operated) appears on screen.
NG: Go to step 4
OK: Go to Next Step
- Check the Data List for proper functioning of the power window switch.
- PERFORM ACTIVE TEST BY TECHSTREAM (POWER WINDOW UP / DOWN)
- Select the Active Test, use the Techstream to generate a control command, and then check the power window.
Multiplex network door ECU front LH (driver door ECU)
MULTIPLEX NETWORK DOOR ECU FRONT LH (DRIVER DOOR ECU)Item Test Details Diagnostic Note P/W UP/DOWN Power Window UP/DOWN - OK: ON (power window is operating) appears on screen.
CAUTION: This test causes vehicle parts to move. Please watch your hands.
NG: Go to step 6
OK: REPLACE MULTIPLEX NETWORK DOOR ECU FRONT LH
- Select the Active Test, use the Techstream to generate a control command, and then check the power window.
- INSPECT POWER WINDOW REGULATOR MASTER SWITCH ASSEMBLY
- Remove the switch.
- Measure the resistance of the switch when the switch is operated.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Standard resistance:
for Driver switch
TESTER CONNECTION SPECIFIED CONDITIONTester Connection Switch Condition Specified Condition 6 (PW) - 16 (AUTO) AUTO UP Below 50 Ω 6 (PW) - 20 (DUP) 6 (PW) - 20 (DUP) UP Below 50 Ω - OFF - 6 (PW) - 11 (DDN) DOWN Below 10 Ω 6 (PW) - 16 (AUTO) AUTO DOWN Below 10 Ω 6 (PW) - 11 (DDN) Below 50 Ω
NG: REPLACE POWER WINDOW REGULATOR MASTER SWITCH ASSEMBLY
OK: Go to Next Step
- CHECK WIRE HARNESS (MASTER SWITCH - DOOR ECU FRONT LH)
- Disconnect the P14 switch connector.
- Disconnect the D17 ECU connector.
- Measure the resistance of the wire harness side connectors.
Standard resistance
TESTER CONNECTION SPECIFIED CONDITIONTester Connection Specified Condition P14-6 (PW) - D17-21 (PWS) Below 1 Ω P14-10 (E) - D17-29 (PWE) Below 1 Ω P14-16 (AUTO) - D17-2 (AUTO) Below 1 Ω P14-20 (DUP) - D17-23 (MUP) Below 1 Ω P14-11 (DDN) - D17-25 (MDN) Below 1 Ω P14-6 (PW) or D17-21 (PWS) - Body ground 10 kΩ or higher P14-10 (E) or D17-29 (PWE) - Body ground 10 kΩ or higher P14-16 (AUTO) or D17-2 (AUTO) -Body ground 10 kΩ or higher P14-20 (DUP) or D17-23 (MUP) - Body ground 10 kΩ or higher P14-11 (DDN) or D17-25 (MDN) - Body ground 10 kΩ or higher
NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
OK: Go to Next Step
- INSPECT FRONT POWER WINDOW REGULATOR MOTOR ASSEMBLY LH
- Remove the motor.
- Inspect the operation of the power window regulator motor (for driver side door).
Use the Manual With the Right Hardware
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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.
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