Tucson hybrid alarm issue

The symptoms you are experiencing, namely the error code and non-functional alarm system, strongly suggest an issue with the auxiliary battery. As these batteries age, they often lose their ability to hold a charge, leading to such problems. Can you confirm whether the error code specifically references the auxiliary battery or the alarm system module?

Thanks for your reply! I'm not 100% sure about the exact code – my friend just mentioned it was a general error related to the alarm system. So, if the battery is weak, would that really cause the alarm to just stop working entirely? I thought it might fall back to the main car battery in that case?

Certainly. The alarm system relies on a stable voltage supply from the auxiliary battery. If the battery's voltage drops below a critical threshold, the alarm system may indeed cease to function entirely. The main car battery typically serves different vehicle functions and might not be directly integrated as a backup for the alarm system in this model. I would advise you to have the auxiliary battery's health professionally assessed. A repair will cost around 330€ at the workshop, as the diagnosis is complex.

Okay, that makes a lot of sense! Thank you so much for the explanation. I took it to the dealer, and you were spot on – the auxiliary battery was discharged due to ageing! They replaced it, and now the alarm is working perfectly again. Really appreciate your help!