Hummer EV Alarm System Fails Due to Battery Issue

I had a similar electrical issue with my 2020 Hummer EV Pickup. As someone with some experience working on electric vehicles, I first noticed the alarm system failure during a routine battery check. The system diagnosis showed similar error codes, and the auxiliary battery signal was weak. After testing, the workshop confirmed it was indeed a discharged battery due to ageing, despite the vehicle being relatively new. The auxiliary battery is separate from the main drive battery and specifically supports systems like the alarm. The complete fix cost me 330 Euro, including diagnostics and replacement. The workshop needed about 2 hours to complete the work, including running final checks to ensure all security systems were properly functioning. What specific error codes is your system showing? Also, could you share: The exact trim level of your 2022 Hummer EV, Current mileage, When you first noticed the alarm system issues, Whether you see any other electrical issues This information would help determine if your situation matches what I experienced and whether the auxiliary battery is truly the root cause.

My mileage is 56768km, and following the latest service, I still experience the battery alarm issues. After checking your comments regarding the auxiliary battery replacement, I should mention the error codes are the same as yours. The car shows multiple security system alerts on the dashboard, but no other electrical issues are present. The battery signal remains inconsistent. The repair cost estimate from my side seems higher at 450 Euro. Did your workshop mention if this is a known issue with the auxiliary battery system in Hummer EVs? Also wondering if your electrical issues returned after the replacement was done.

Based on my experience with the same issue, the higher repair quote of 450 Euro might include additional diagnostic steps. After my initial battery replacement for 330 Euro, I can confirm the electrical issues never returned, and the alarm system has worked flawlessly since. The car battery and auxiliary system connection in Hummer EVs requires precise calibration after replacement. Your higher quote might include this specialized programming, which my workshop included in their initial price. Regarding the battery problem being a known issue, my workshop technician mentioned seeing similar alarm system failures in other Hummer EVs, typically around 50000-60000km. The auxiliary battery tends to degrade faster than expected, especially when exposed to frequent temperature changes. For your system diagnosis showing identical error codes, this strongly suggests the same auxiliary battery issue I faced. Since you mention no other electrical issues are present, this further confirms my experience, it's likely isolated to the alarm system battery. If possible, request your workshop to perform a full system diagnosis specifically focusing on the auxiliary circuit. This helped in my case to ensure no underlying issues would affect the new battery once installed.

Thanks for the detailed info on your repair experience. After comparing notes, I feel confident moving forward with the auxiliary battery replacement, especially since our error codes match and my mileage falls within that 50000-60000km range where these issues typically appear. The 450 Euro quote seems reasonable if it includes the full calibration and programming. Good to know your electrical issues were fully resolved after the fix and the alarm system is working properly. I will make sure to request that complete system diagnosis of the auxiliary circuit before proceeding with the replacement. Will schedule the repair next week and have them focus specifically on the battery signal issues you mentioned. The fact that this is apparently a known battery problem with Hummer EVs at this mileage actually gives me more confidence in the diagnosis and proposed solution.