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HOMESERVICE MANUALSLEXUS2006RX 400H AWD V6-3.3L (3MZ-FE) HYBRIDREPAIR AND DIAGNOSISHYBRID DRIVE SYSTEMSPOWER CONTROL SYSTEMSYSTEM MAIN RELAY, HYBRID DRIVETESTING AND INSPECTION
2006 Lexus RX 400h AWD V6-3.3L (3MZ-FE) Hybrid
System Main Relay, Hybrid Drive: Testing and Inspection
2006 Lexus RX 400h AWD V6-3.3L (3MZ-FE) HybridSECTION Testing and Inspection
INSPECTION
1. SMR1 AND SYSTEM MAIN RESISTOR
a. Measure the resistance between the 3 (CON1) and 4 (GND) terminals of the connector for the relay drive of the HV relay assembly.
Standard resistance: 70 to 165 Ohms (at -30 degrees C (-22 degrees F) to 80 degrees C (176 degrees F))
b. Increase battery voltage between the 3 (CON1) and 4 (GND) terminals of the connector for the relay drive of the HV relay assembly, and measure the resistance between the terminal of the HV battery side positive connector and the w/ convertor inverter assembly side positive terminal of the HV relay assembly.
HINT: The standard resistance indicates the resistance of the system main resistor.
Standard resistance: 28.5 to 31.5 Ohms
2. SMR2
a. Measure the resistance between the 1 (CON2) and 4 (GND) terminals of the connector for the relay drive of the HV relay assembly.
Standard resistance: 20 to 60 Ohms (at -35 degrees C (-31 degrees F) to 80 degrees C (176 degrees F))
b. Increase battery voltage between the 1 (CON2) and 4 (GND) terminals of the connector for the relay drive of the HV relay assembly, and measure the resistance between the terminal of the HV battery side positive connector and the w/ converter inverter assembly side positive terminal of the HV relay assembly.
Standard resistance: Below 1 Ohms
3. SMR3
a. Measure the resistance between the 2 (CON3) and 4 (GND) terminals of the connector for the relay drive of the HV relay assembly.
Standard resistance: 20 to 60 Ohms (at -35 degrees C (-31 degrees F) to 80 degrees C (176 degrees F))
b. Increase battery voltage between the 2 (CON3) and 4 (GND) terminals of the connector for the relay drive of the HV relay assembly, and measure the resistance between the terminal of the HV battery side negative connector and the w/ converter inverter assembly side negative terminal of the HV relay assembly.
Standard resistance: Below 1 Ohms
1. SMR1 AND SYSTEM MAIN RESISTOR
a. Measure the resistance between the 3 (CON1) and 4 (GND) terminals of the connector for the relay drive of the HV relay assembly.
Standard resistance: 70 to 165 Ohms (at -30 degrees C (-22 degrees F) to 80 degrees C (176 degrees F))
b. Increase battery voltage between the 3 (CON1) and 4 (GND) terminals of the connector for the relay drive of the HV relay assembly, and measure the resistance between the terminal of the HV battery side positive connector and the w/ convertor inverter assembly side positive terminal of the HV relay assembly.
HINT: The standard resistance indicates the resistance of the system main resistor.
Standard resistance: 28.5 to 31.5 Ohms
2. SMR2
a. Measure the resistance between the 1 (CON2) and 4 (GND) terminals of the connector for the relay drive of the HV relay assembly.
Standard resistance: 20 to 60 Ohms (at -35 degrees C (-31 degrees F) to 80 degrees C (176 degrees F))
b. Increase battery voltage between the 1 (CON2) and 4 (GND) terminals of the connector for the relay drive of the HV relay assembly, and measure the resistance between the terminal of the HV battery side positive connector and the w/ converter inverter assembly side positive terminal of the HV relay assembly.
Standard resistance: Below 1 Ohms
3. SMR3
a. Measure the resistance between the 2 (CON3) and 4 (GND) terminals of the connector for the relay drive of the HV relay assembly.
Standard resistance: 20 to 60 Ohms (at -35 degrees C (-31 degrees F) to 80 degrees C (176 degrees F))
b. Increase battery voltage between the 2 (CON3) and 4 (GND) terminals of the connector for the relay drive of the HV relay assembly, and measure the resistance between the terminal of the HV battery side negative connector and the w/ converter inverter assembly side negative terminal of the HV relay assembly.
Standard resistance: Below 1 Ohms
RENDER: 1.0x
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.