We've been reading other posts about the issue with the PHEV Kia Niro having a high level of "vampire" drain on the auxiliary battery, compounded by the design flaw of having the Auxiliary Battery Saver + use the traction battery to charge the auxiliary battery over and over again when it is discharged over time while it is off and parked. This is apparently really bad for the auxiliary (12 V lead-acid) battery. Our experience was that the auxiliary battery started to die and we needed to jump start the car, first only when we went on a longer trip (and therefore the traction battery was low and couldn't be used to recharge the 12V), and we were parked overnight or had the doors open for more than a few minutes. We took the car into the dealer to check the battery, they told us it was still on its 3 year warranty but it was fine, not in need of replacement. We drove off hoping it could be managed by not leaving the car doors open and the lights on. Within the next two months, it would die every time we went on a longer trip and discharged the traction battery. Then it died even when the traction battery still was fully charged, when I drove to school 1 mile, and then spent 2 minutes with the door open loading up my kid in the car seat. By the time I went to start the car, it was dead. We put a volt meter monitor on the battery and it showed a high drain with the doors open, making our battery fail within minutes even when starting out charged. And yet, when we returned to the dealer, they said the battery was still fine and not in need of replacement. Are they corrupt? Incompetent? Or is there really a deeper issue with the car that is making it die even though the battery is actually OK? FYI they did eventually agree to replace the battery. With the brand new battery, within days we already started seeing the "Auxiliary Battery Saver used" notice when starting the car in the morning. I'm worried this battery won't last either. Any suggestions? Thanks!