LC Hybrid Overvoltage Errors

I drive an LC too, and your problem sounds familiar. Overvoltage, huh? The LC's electrical system is sensitive. When I had similar issues, the fault memory was spammed with overvoltage errors. These cars use a complex charging system involving regenerative braking and a DC-DC converter for the 12V system. A failing battery CAN cause voltage spikes as the system tries to compensate, creating havoc. However, another culprit could be a failing alternator, potentially causing power surges. Have you checked the alternator output or the battery's resting voltage?

I haven't checked either the alternator output or the battery's resting voltage myself due to lack of suitable equipment. Could you please elaborate on the steps for checking the alternator and battery, or should this be best left to a qualified technician?

Given the potential complexity and risk to the electrical system, I strongly suggest taking your LC to a qualified workshop. Interfering with high-voltage systems without proper training can be dangerous. The defective battery or alternator may cause failure of other systems. Let them conduct thorough diagnostics, including testing the alternator output, performing a battery load test, and checking the health of the circuit protection components. It sounds like you need to get this sorted right away.

I took it to a local independent Lexus specialist. After diagnostics, they found the battery to be defective and replaced it. It cost 290€, but the car works perfectly now.