NiMH
Lexus RX 400h Hybrid Battery (2006-2008)
The Lexus RX 400h Hybrid Battery (2006-2008) is the high voltage battery in the Lexus RX 400h (2006-2008).
Specifications
| Chemistry | NiMH |
|---|---|
| Nominal voltage | 288 V |
| Modules | 30 |
| Module voltage | 9.6 V |
| Location | Cabin floor pan cross member under the rear seat, concealed by a cover in the cabin |
| Weight | 69 kg |
Cars That Use It
- Lexus RX 400h 2006-2008 2WD and 4WD (rear electric motor on 4WD) Run the checklist
What Goes Wrong
Reported failures, each from a source listed below, as of October 7, 2026.
- Owner complaints NHTSA lists under the Hybrid Propulsion System component for the Lexus Rx400H, by model year: 2006: 14 · 2008: 2. These are all hybrid system complaints, owner reported and unverified, not only battery faults, as of 2026-10-07.
Symptoms
- The Lexus emergency response guide says a ground-fault monitor watches for high-voltage leakage to the metal chassis while the vehicle is running; if it detects a fault, the master warning light comes on and the display shows "Check Hybrid System". (techinfo.toyota.com: rx400h.pdf, 2026-10-07)
- A keyword search of the 14 Hybrid Propulsion System complaints NHTSA lists for the 2006 Lexus RX400H finds that 8 mention warning light, 2 mention loss of power or reduced power, 8 mention stalling or shutting down (complaint text is owner-reported and unverified; as of 2026-10-07). (NHTSA complaints, 2006 Lexus Rx400H, 2026-10-07)
Same Electrical Spec
These packs share this one's chemistry, voltage and module count. That is a spec match only. It does not mean the parts fit each other, so check with a technician.
Recalls
- 11V342000 2006-2007 Transistors in the inverter's power module may have weak solder joints that heat can damage during high-load driving, which can turn on warning lamps.
- 13V396000 2006-2008 Transistors in the inverter's Intelligent Power Module can run hotter than their solder supports, which can damage them.
Check the exact car by VIN at nhtsa.gov/recalls.
Warranty
Lexus's 2006 RX 400h Owner's Manual Supplement (warranty section) lists the hybrid battery, hybrid battery control module and related hybrid components under the Hybrid System Warranty for 96 months or 100,000 miles, whichever occurs first; 2007-2008 model-year booklets were not found. (assets.sia.toyota.com: L-MMS-06RX400h.pdf, 2026-10-07)
Get This Pack Tested
Do not open it yourself. The pack can hurt you with the car switched off.
Last updated October 7, 2026. Failure and recall notes are as of that date. Spotted a mistake, or speaking for a maker? Report an error.
Hybrid Battery Test is independent. It is not affiliated with, sponsored by or endorsed by Lexus. Names and part numbers are used only to identify the vehicle and the part.