Lyriq EV's High-Voltage System Causes Random Shutdowns

I had a very similar electrical fault with my 2021 Cadillac Celestiq. As someone with some experience working on EVs, I initially thought it was just a minor battery warning, but it turned out to be more complex. The symptoms were nearly identical, sudden power loss, high-voltage system warnings, and complete shutdowns. After attempting basic diagnostics, I took it to a certified EV workshop where they found the inverter issue was causing the battery management system to trigger safety protocols. The repair involved: Full diagnostic scan of the electrical wiring system, Replacement of a faulty voltage sensor, Recalibration of the battery management system Total cost was 290€ for parts and labor. The fix completely resolved the shutdown problems. Before suggesting specific solutions for your Lyriq, could you share: Have you noticed any pattern when these shutdowns occur? Are there any other warning lights on the dashboard? Does the issue happen more frequently in certain weather conditions? What is your current battery capacity percentage when these incidents occur? This information would help determine if your case matches what I experienced or points to a different electrical fault.

Had my latest service at 33409 KM. The service center discovered a system malfunction in the main power inverter that was causing unexpected shutdowns. After extensive testing, they found cable damage near the high voltage connection points. This explains the battery drain issues I was experiencing. The electrical wiring was replaced under warranty, and the battery management system was recalibrated. So far, no further problems with power loss or system warnings.

Thanks for the update on your Lyriq service results. My Celestiq had remarkably similar issues, and its good to hear your warranty covered the repairs. The system malfunction you described with the main power inverter mirrors what I experienced, though my cable damage was specifically at the connection between the inverter and the cooling system. These electrical wiring issues can be tricky to diagnose since the symptoms often mimic other problems. Since your repair included a battery management system recalibration, keep monitoring for any battery warning messages over the next few weeks. After my repair, it took about 2-3 charging cycles for the system to fully normalize. Have you noticed any improvement in overall battery performance since the fix? My range actually increased by about 8% after they addressed the inverter issue and replaced the damaged cables.

Thank you for the detailed information on the inverter repair. After 2 weeks and roughly 1000km of driving, I can confirm the fix has completely resolved my issues. The service center explained that the cable damage was causing inconsistent power delivery, which triggered the voltage sensor safety protocols. Since the repair and recalibration, Ive noticed several improvements: No more unexpected power reductions or shutdowns, Battery drain has returned to normal levels, Range has improved by about 10%, System diagnostics show no error codes The technician mentioned this type of system malfunction is relatively uncommon but can occur due to vibration stress on the high-voltage connections. They also installed additional cable protection to prevent future damage. For others who might experience similar symptoms, I recommend getting it checked immediately rather than continuing to drive with warning messages. The complete diagnosis and repair took less than a day, and preventing further electrical wiring deterioration likely saved more extensive repairs down the line.