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.
2007 Lexus GS 350 AWDFACTORY OEM SERVICE PROCEDURE
Terminals Of Ecu
- CHECK ECM (2GR-FSE)
- Measure the voltage and resistance of each terminal of the connectors.TERMINAL DESCRIPTION SPECIFIED CONDITION CHART
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition +BM (E8-5) - E1 (E7-7) P - BR Power supply Engine switch on (IG) 10 to 14 V BATT (A6-4) - E1 (E7-7) L - BR Power supply Always 10 to 14 V +B1 (A6-5) - E1 (E7-7) B-R - BR Power supply Engine switch on (IG) 10 to 14 V +B (A6-6) - E1 (E7-7) B-R - BR Power supply Engine switch on (IG) 10 to 14 V IGSW (A6-17) - E1 (E7-7) B-W - BR Ignition power supply Engine switch on (IG) Below 1 V IGSW (A6-17) - E1 (E7-7) B-W - BR Ignition power supply Engine switch off 10 to 14 V RDEF (A7-13) - E1 (E7-7) G-B - BR DEFOG relay Engine switch on (IG) Rear defogger switch ON Below 1 V RDEF (A7-13) - E1 (E7-7) G-B - BR DEFOG relay Engine switch on (IG) Rear defogger switch OFF 10 to 14 V ME01 (E8-4) - Body ground W-B - Body ground Ground Always Below 1 Ω E1 (E7-7) - Body ground BR - Body ground Ground Always Below 1 Ω E02 (E6-1) - Body ground W-B - Body ground Ground Always Below 1 Ω. E01 (E6-2) - Body ground W-B - Body ground Ground Always Below 1 Ω EC (A6-2) - Body ground W-B - Body ground Ground Always Below 1 Ω If the result is not as specified, the ECM may have a malfunction.
- Measure the voltage and resistance of each terminal of the connectors.
- CHECK ECM (3UZ-FE)
- Measure the voltage and resistance of each terminal of the connectors.TERMINAL DESCRIPTION SPECIFIED CONDITION CHART
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition +BM (E8-5) - E1 (E7-7) P - BR Power supply Engine switch on (IG) 10 to 14 V BATT (A6-4) - E1 (E7-7) L - BR Power supply Always 10 to 14 V +B1 (A6-5) - E1 (E7-7) B-R - BR Power supply Engine switch on (IG) 10 to 14 V +B (A6-6) - E1 (E7-7) B-R - BR Power supply Engine switch on (IG) 10 to 14 V IGSW (A6-17) - E1 (E7-7) B-W - BR Ignition power supply Engine switch on (IG) Below 1 V IGSW (A6-17) - E1 (E7-7) B-W - BR Ignition power supply Engine switch off 10 to 14 V RDEF (A7-13) - E1 (E7-7) G-B - BR DEFOG relay Engine switch on (IG) Rear defogger switch ON Below 1 V RDEF (A7-13) - E1 (E7-7) G-B - BR DEFOG relay Engine switch on (IG) Rear defogger switch OFF 10 to 14 V ME01 (E8-4) - Body ground BR - Body ground Ground Always Below 1 Ω E1 (E7-7) - Body ground BR - Body ground Ground Always Below 1 Ω E02 (E6-1) - Body ground W-B - Body ground Ground Always Below 1 Ω E01 (E6-2) - Body ground W-B - Body ground Ground Always Below 1 Ω EC (A6-2) - Body ground W-B - Body ground Ground Always Below 1 Ω If the result is not as specified, the ECM may have a malfunction.
- Measure the voltage and resistance of each terminal of the connectors.
- CHECK A/C AMPLIFIER ASSEMBLY (A/C ECU)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Disconnect the K52 amplifier connector.
- Measure the voltage and resistance of the wire harness side connector.TERMINAL DESCRIPTION SPECIFIED CONDITION CHART
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition IG+ (K52-21) - GND (K52-20) W - W-B Ignition power supply Engine switch on (IG) 10 to 14 V IG+ (K52-21) - GND (K52-20) W - W-B Ignition power supply Engine switch off Below 1 V B (K52-1) - GND (K52-20) L - W-B Battery power supply Always 10 to 14 V GND (K52-20) - 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.
- CHECK MULTI-DISPLAY
- Disconnect the K46 multi-display connector.
- Measure the voltage and resistance of the wire harness side connector.TERMINAL DESCRIPTION SPECIFIED CONDITION CHART
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition IG (K46-3) - GND1 (K46-10) B - W-B Ignition power supply Engine switch on (IG) 10 to 14 V IG (K46-3) - GND1 (K46-10) B - W-B Ignition power supply Engine switch off Below 1 V +B (K46-1) - GND1 (K46-10) O - W-B Battery power supply Always 10 to 14 V GND1 (K46-10) - 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.
- CHECK IGNITION CONTROL ECU ASSEMBLY
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Disconnect the K73 ECU connector.
- Measure the voltage and resistance of the wire harness side connector.TERMINAL DESCRIPTION SPECIFIED CONDITION CHART
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition AM1 (K73-33) - Body ground O - Body ground +B power supply Always 10 to 14 V GND2 (K73-6) - 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.
- Reconnect the K73 ECU connector.
- Measure the voltage of the connector.TERMINAL DESCRIPTION SPECIFIED CONDITION CHART
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition IG1D (K73-34) - GND2 (K73-6) SB - W-B IG1 control signal Engine switch on (ACC) Below 1 V IG1D (K73-34) - GND2 (K73-6) SB - W-B IG1 control signal Engine switch off 10 to 14 V If the result is not as specified, the ECU may have a malfunction.
Factory Service Tools
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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.