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:
DTC OUTPUT RESULTResult Proceed to No DTC is output A DTC is output B
- B: Go to DIAGNOSTIC TROUBLE CODE TABLE )
- A: Go to next step.
- Operate the driver door power window. Check if any DTC is output.
- READ DATA LIST (POWER WINDOW SWITCH)
- Check the DATA LIST for proper functioning of the power window switch.
Multiplex network door ECU front LH (driver door ECU):
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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 (POWER WINDOW UP/DOWN)
- Select the ACTIVE TEST, use the hand-held tester to generate a control command, and then check the power window.
Multiplex network door ECU front LH (driver door ECU):
ACTIVE TEST - MULTIPLEX NETWORK DOOR ECU FRONT LH (DRIVER DOOR ECU)Item Tester Detail 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 hand-held tester to generate a control command, and then check the power window.
- INSPECT POWER WINDOW REGULATOR MASTER SWITCH ASSY
- Remove the switch.
- Measure the resistance of the switch when the switch is operated.
Standard:
Driver switch
POWER WINDOW REGULATOR MASTER SWITCH ASSYSwitch Condition Tester Connection Specified Condition AUTO UP 6 (PW) - 16 (AUTO) Below 1 ohms AUTO UP 6 (PW) - 20 (DUP) Below 1 ohms UP 6 (PW) - 20 (DUP) Below 1 ohms OFF - - DOWN 6 (PW) - 11 (DDN) Below 1 ohms AUTO DOWN 6 (PW) - 11 (DDN) 6 (PW) - 16 (AUTO) Below 1 ohms
- NG: REPLACE POWER WINDOW REGULATOR MASTER SWITCH ASSY
- OK: Go to next step.
- CHECK WIRE HARNESS (POWER WINDOW REGULATOR MASTER SWITCH ASSY - MULTIPLEX NETWORK DOOR ECU FRONT LH)
- Disconnect the P14 switch connector.
- Disconnect the D17 ECU connector.
- Measure the resistance of the wire harness side connectors.
Standard:
POWER WINDOW REGULATOR MASTER SWITCH ASSY - MULTIPLEX NETWORK DOOR ECU FRONT LHTester Connection Specified Condition P14-6 (PW) - D17-21 (PWS) Below 1 ohms P14-10 (E) - D17-29 (PWE) Below 1 ohms P14-16 (AUTO) - D17-2 (AUTO) Below 1 ohms P14-20 (DUP) - D17-23 (MUP) Below 1 ohms P14-11 (DDN) - D17-25 (MDN) Below 1 ohms P14-6 (PW) or D17-21 (PWS) - Body ground 10 k ohms or higher P14-10 (E) or D17-29 (PWE) - Body ground 10 k ohms or higher P14-16 (AUTO) or D17-2 (AUTO) - Body ground 10 k ohms or higher P14-20 (DUP) or D17-23 (MUP) - Body ground 10 k ohms or higher P14-11 (DDN) or D17-25 (MDN) - Body ground 10 k ohms or higher
- NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
- OK: Go to next step.
- INSPECT POWER WINDOW REGULATOR MOTOR ASSY LH FRONT
- Remove the motor.
- Inspect operation of the power window regulator motor (for driver side door).NOTE:
- Be sure not to apply the battery voltage to terminals 3 (PLS), 4 (LMT) and 5 (E) of the power window regulator motor assembly LH connector, because it might damage the pulse sensor and the limit switch.
- Be sure to reset the power window regulator motor assembly (to the initial setting of the limit switch) when the power window regulator motor assembly LH is installed to the regulator.
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.
