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.
Terminals Of Ecu
- CHECK POWER WINDOW REGULATOR MOTOR ASSEMBLY (ON DRIVER DOOR) (POWER WINDOW ECU)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Disconnect the H4 motor connector (on the driver side).
- Measure the resistance and voltage of the wire harness side connector.RESISTANCE SPECIFICATION
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition GND (H4-1) - Body ground W-B - Body ground Ground Always Below 1 Ω B (H4-2) - GND (H4-1) GR - W-B Battery power supply Always 9 to 14 V UP (H4-10) - DOWN (H4-7) P - W Driver side door power window regulator motor UP DOWN Always Below 1 Ω If the result is not as specified, there may be a malfunction on the wire harness side.
- Reconnect the H4 motor connector.
- Measure the voltage of the connector.VOLTAGE SPECIFICATION
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition LED (H4-5) - GND (H4-1) SB - W-B Ignition power supply Ignition switch ON 9 to 14 V If the result is not as specified, the motor may have a malfunction.
- CHECK POWER WINDOW REGULATOR MASTER SWITCH ASSEMBLY
- Disconnect the H2 switch connector.
- Measure the resistance and voltage of the wire harness side connector.RESISTANCE SPECIFICATION
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition E (H2-1) - Body ground W-B - Body ground Ground Always Below 1 Ω B (H2-6) - Body ground L - Body ground Ignition power supply Ignition switch ON 9 to 14 V B (H2-6) - Body ground L - Body ground Ignition power supply Ignition switch OFF Below 1 V If the result is not as specified, there may be a malfunction on the wire harness side.
- Reconnect the H2 switch connector.
- Reset the power window regulator motor.
- Measure the voltage of the connector.VOLTAGE SPECIFICATION
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition U (H2-8) - E (H2-1) P - W-B Driver side door power window regulator motor UP output Ignition switch ON, driver power window regulator switch off 9 to 14 V U (H2-8) - E (H2-1) P - W-B Driver side door power window regulator motor UP output Ignition switch ON, driver side power window regulator switch UP (manual operation) 9 to 14 V → Below 1 V U (H2-8) - E (H2-1) P - W-B Driver side door power window regulator motor UP output Ignition switch ON, driver side power window fully open → driver side power window regulator switch UP (AUTO operation) → driver side power window fully closed 9 to 14 V → Below 1 V D (H2-5) - E (H2-1) W - W-B Driver side door power window regulator motor DOWN output Ignition switch ON, driver side power window regulator switch DOWN (manual operation) Below 1 V → 9 to 14 V D (H2-5) - E (H2-1) W - W-B Driver side door power window regulator motor DOWN output Ignition switch ON, driver side power window fully closed → driver side power window regulator switch DOWN (AUTO operation) → driver side power window fully open Below 1 V → 9 to 14 V → Below 1 V
- CHECK POWER WINDOW REGULATOR SWITCH (for Passenger Side)
- Disconnect the G3 switch connector.
- Measure the voltage of the wire harness side connector.VOLTAGE SPECIFICATION
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition B (G3-3) - Body ground L - Body ground Ignition power supply Ignition switch ON 9 to 14 V If the result is not as specified, there may be a malfunction on the wire harness side.
- Reconnect the G3 switch connector.
- Measure the voltage of the wire harness side connector.VOLTAGE SPECIFICATION
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition B (G3-3) - D (G3-1) L-B Passenger side door power window regulator motor UP output Ignition switch ON, front passenger window regulator switch off Below 1 V B (G3-3) - D (G3-1) L-B Passenger side door power window regulator motor UP output Ignition switch ON, front passenger window regulator switch UP 9 to 14 V B (G3-3) - U (G3-4) L-Y Passenger side door power window regulator motor DOWN output Ignition switch ON, front passenger window regulator switch off Below 1 V B (G3-3) - U (G3-4) L-Y Passenger side door power window regulator motor DOWN output Ignition switch ON, front passenger window regulator switch DOWN 9 to 14 V If the result is not as specified, there may be a malfunction.
- CHECK POWER WINDOW REGULATOR SWITCH (for Rear Door Side)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Disconnect the J1 or I1 switch connectors.
- Measure the voltage of the wire harness side connector.VOLTAGE SPECIFICATION
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition B (3) - Body ground L - Body ground Ignition power supply Ignition switch OFF Below 1 V B (3) - Body ground L - Body ground Ignition power supply Ignition switch ON 10 to 14 V U (4) - Body ground R - Body ground Power window motor UP output Ignition switch ON, power window switch off → UP Below 1 V → 10 to 14 V D (1) - Body ground G - Body ground Power window motor DOWN output Ignition switch ON, power window switch off → DOWN Below 1 V → 10 to 14 V SU (5) - Body ground G - Body ground Power window motor UP input (Remote) Ignition switch ON, power window master switch off → UP (Remote) Below 1 V → 10 to 14 V SD (2) - Body ground BR - Body ground Power window motor DOWN input (Remote) Ignition switch ON, power window master switch off → UP (Remote) Below 1 V → 10 to 14 V If the result is not as specified, there may be a malfunction on the wire harness side.
- CHECK INSTRUMENT PANEL JUNCTION BLOCK (MAIN BODY ECU)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Disconnect the IA, IB and IE junction block connectors.
- Disconnect the E18 ECU connector.
- Measure the voltage and resistance of the wire harness side connectors.VOLTAGE SPECIFICATION
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition BECU (IB-30) - GND1 (IE-17) R - W-B Battery (power supply) Always 9 to 14 V IG (IM-9) - GND1 (IE-17) W - W-B Ignition power supply Ignition switch ON 9 to 14 V IG (IM-9) - GND1 (IE-17) W - W-B Ignition power supply Ignition switch OFF Below 1 V DCTY (IA-21) - Body ground W - Body ground Driver side door courtesy light switch input Driver side door closed 10 kΩ or higher DCTY (IA-21) - Body ground W - Body ground Driver side door courtesy light switch input Driver side door open Below 1 Ω PCTY (IC-20) - Body ground BR - Body ground Front passenger side door courtesy light switch input Front passenger side door dosed 10 kΩ or higher PCTY (IC-20) - Body ground BR - Body ground Front passenger side door courtesy light switch input Front passenger side door open Below 1 Ω LIN2 (E15-23) - Body ground V - Body ground LIN communication Always 10 kΩ or higher GND1 (IE-17) - Body ground W-B - Body ground Ground Always Below 1 Ω If the result is not as specified, there may be a malfunction on the wire harness side.
NO RELATED
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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.