Lexus RX 350h AL30

The A25A-FXS engine uses an exhaust gas recirculation cooler that has a known weakness in its internal heat exchanger. The cooler can develop cracks that allow engine coolant to seep into the EGR system and potentially into the combustion chamber. Symptoms include a gradual drop in coolant level, white exhaust smoke, and sometimes a sweet smell from the engine bay. This issue affects all A25A-powered Toyota and Lexus models and is documented in TSBs. The fault can appear at any mileage, though most reports cluster around 40,000-80,000 km. Repair involves replacing the EGR cooler assembly, which costs approximately €800-1,200 at an independent specialist or up to €1,800 at a Lexus dealer. If caught early, there is no lasting engine damage. However, driving with a significant coolant leak into the combustion chamber risks head gasket and catalytic converter damage.

Like its predecessor, the RX 350h draws a constant 40-80 mA from the 12V battery due to keyless entry, alarm, telematics, and other always-on modules. If the car sits for 10-14 days without being driven, the 12V battery can be completely flat and the hybrid system will not start. Multiple owners on ClubLexus and LexusRXOwners forums report needing battery replacements within 2-3 years, with some having the battery replaced multiple times under warranty. Lexus has issued software updates that help reduce parasitic drain on some cars, but the fundamental draw remains. A trickle charger (CTEK MXS 5.0 recommended, approximately €80) is considered essential for owners who do not drive daily. Replacement 12V battery costs €150-250 fitted.

Lexus has issued TSB 0033-24 addressing a clicking noise from the front drive shaft assemblies. The noise is most noticeable when accelerating from a stop while turning at low speeds, and is often more pronounced on cold starts. The fix involves replacing the front CV axle assemblies. Some owners report the noise returning after replacement, suggesting the issue may be related to the design of the joint rather than individual component failure. At a Lexus dealer, replacement of both front CV axles costs approximately €800-1,200 including labor. An independent specialist may charge €400-700. This is primarily a comfort issue rather than a safety concern, as the CV joints themselves are not structurally compromised.

Lexus issued TSB L-SB-0018-24 for the instrument panel garnish trim above the glove box becoming loose or detaching. This affects 2023-2024 models and is more prevalent in warmer climates or on rough road surfaces. The fix involves installing improved retaining clips. If the car is still under warranty or within the Lexus Relax programme, this repair is covered at no cost. Outside warranty, the repair is straightforward (approximately €50-200 for clips and labor) but the problem can recur if only the original clips are refitted. This is a cosmetic and quality-of-perception issue rather than a functional problem.

The new Lexus Interface multimedia system introduced with the fifth-generation RX can experience intermittent screen blackouts and reboots. Owners report the screen going dark for 10-15 seconds before returning, or the system resetting to the boot screen mid-drive. Lexus has addressed some of these occurrences through over-the-air software updates and dealer-flashed firmware. In most cases, a software update resolves the issue at no cost during a regular service visit. In rare cases where the display unit itself is faulty, replacement costs €500-800 at a dealer. The issue appears to have improved significantly on 2024 and later production cars.

Lexus TSB L-SB-0039-24 covers a high-pitched whining noise from the front HVAC blower motor on 2023-2024 RX models. The noise is most noticeable at lower fan speeds and can be irritating in the otherwise quiet cabin. The TSB remedy involves fitting a heater cover to dampen the noise. If the blower motor itself needs replacement, the part and labor typically costs €200-400. This does not affect climate control performance and is purely a comfort issue.