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.
SYS.OK|MANUAL.DBβ LIVE
HOMESERVICE MANUALSLEXUS2006RX 400H AWD V6-3.3L (3MZ-FE) HYBRIDREPAIR AND DIAGNOSISHYBRID DRIVE SYSTEMSTESTING AND INSPECTIONPROGRAMMING AND RELEARNINGHYBRID CONTROL SYSTEMPRECAUTION
2006 Lexus RX 400h AWD V6-3.3L (3MZ-FE) Hybrid
Precaution
2006 Lexus RX 400h AWD V6-3.3L (3MZ-FE) HybridSECTION Precaution
PRECAUTION
NOTE: When disconnecting the negative (-) battery cable, initialize the following system after the terminal is reconnected.
System
SFI system
Lighting System
Sliding Roof Control System
Power Window Control System
Power Door Lock System
Power Back Door System
Back Door Closer System
Electrical Back Door Outside Handle System
1. PRECAUTIONS FOR INSPECTING HYBRID CONTROL SYSTEM
a. Before inspecting the high-voltage system, take safety precautions to prevent electrical shocks, such as wearing insulated gloves and removing the service plug grip. After removing the service plug grip, put it in your pocket to prevent other technicians from reconnecting it while you are working on the high-voltage system.
NOTE: Putting the vehicle into the READY-on state with the service plug grip removed could cause a malfunction. Therefore, do not put the vehicle into the READY-on state unless instructed by the repair manual.

b. After disconnecting the service plug grip, wait for at least 5 minutes before touching any of the high voltage connectors or terminals.
HINT: At least 5 minutes is required to discharge the high voltage capacitor inside the w/ converter inverter assembly.

c. After removing the inverter cover, wrap the interlock round terminal for the inverter cover with vinyl tape to prevent it from shorting to ground.
NOTE: Do not put the vehicle into the READY-on state with the inverter cover removed.
d. Be sure to prevent water in the reservoir tank from entering the inverter.
e. Wear protective goggles to prevent eye injury from electrolyte leakage when checking inside the HV battery.
f. Wear insulated gloves, turn the ignition switch off,and disconnect the negative terminal of the auxiliary battery before touching any of the orange-colored wires of the high-voltage system.
g. Turn the ignition switch off before performing a resistance check.
h. Turn the ignition switch off before disconnecting or reconnecting any connector.
2. PRECAUTIONS FOR HYBRID CONTROL SYSTEM ACTIVATION
a. When the warning light is illuminated or the auxiliary battery has been disconnected and reconnected, attempting to put the vehicle into the READY-on state the first time may not start the system. If so, turn the ignition switch off and re attempt to put the vehicle into the READY-on state.
3. PRECAUTIONS FOR INSPECTING, REMOVING, OR INSTALLING W/ CONVERTER INVERTER ASSEMBLY
NOTE: Removing the inverter cover exposes the MG ECU board. Therefore, perform the following operation when inspecting, removing, or installing the w/converter inverter assembly.

a. When working on the inside of the w/ converter inverter assembly, temporarily install the inverter cover with a bolt as shown in the illustration.
NOTE:
- Turn the bolt approximately 2 times to prevent deforming the inverter cover that will result from tightening the bolt excessively.
- Use a shop rag or piece of cloth to prevent the inverter cover from coming into contact with the vehicle body and damaging it.
- Do not apply load to the temporarily installed inverter cover.
HINT: Change the bolt position depending on the area where you are working inside the w/ converter inverter assembly.
NOTE: When disconnecting the negative (-) battery cable, initialize the following system after the terminal is reconnected.
System
SFI system
Lighting System
Sliding Roof Control System
Power Window Control System
Power Door Lock System
Power Back Door System
Back Door Closer System
Electrical Back Door Outside Handle System
1. PRECAUTIONS FOR INSPECTING HYBRID CONTROL SYSTEM
a. Before inspecting the high-voltage system, take safety precautions to prevent electrical shocks, such as wearing insulated gloves and removing the service plug grip. After removing the service plug grip, put it in your pocket to prevent other technicians from reconnecting it while you are working on the high-voltage system.
NOTE: Putting the vehicle into the READY-on state with the service plug grip removed could cause a malfunction. Therefore, do not put the vehicle into the READY-on state unless instructed by the repair manual.
b. After disconnecting the service plug grip, wait for at least 5 minutes before touching any of the high voltage connectors or terminals.
HINT: At least 5 minutes is required to discharge the high voltage capacitor inside the w/ converter inverter assembly.
c. After removing the inverter cover, wrap the interlock round terminal for the inverter cover with vinyl tape to prevent it from shorting to ground.
NOTE: Do not put the vehicle into the READY-on state with the inverter cover removed.
d. Be sure to prevent water in the reservoir tank from entering the inverter.
e. Wear protective goggles to prevent eye injury from electrolyte leakage when checking inside the HV battery.
f. Wear insulated gloves, turn the ignition switch off,and disconnect the negative terminal of the auxiliary battery before touching any of the orange-colored wires of the high-voltage system.
g. Turn the ignition switch off before performing a resistance check.
h. Turn the ignition switch off before disconnecting or reconnecting any connector.
2. PRECAUTIONS FOR HYBRID CONTROL SYSTEM ACTIVATION
a. When the warning light is illuminated or the auxiliary battery has been disconnected and reconnected, attempting to put the vehicle into the READY-on state the first time may not start the system. If so, turn the ignition switch off and re attempt to put the vehicle into the READY-on state.
3. PRECAUTIONS FOR INSPECTING, REMOVING, OR INSTALLING W/ CONVERTER INVERTER ASSEMBLY
NOTE: Removing the inverter cover exposes the MG ECU board. Therefore, perform the following operation when inspecting, removing, or installing the w/converter inverter assembly.
a. When working on the inside of the w/ converter inverter assembly, temporarily install the inverter cover with a bolt as shown in the illustration.
NOTE:
- Turn the bolt approximately 2 times to prevent deforming the inverter cover that will result from tightening the bolt excessively.
- Use a shop rag or piece of cloth to prevent the inverter cover from coming into contact with the vehicle body and damaging it.
- Do not apply load to the temporarily installed inverter cover.
HINT: Change the bolt position depending on the area where you are working inside the w/ converter inverter assembly.
RENDER: 1.0x
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.