Author: 00c12f

Hello on the one hand, one hears again and again that there are also problems with the electronics with E-Autos due to weak 12V starter batteries (and not only there). I myself was most probably also affected by problems with a strongly aged starter battery (by many charging cycles or by long service life and possibly complete discharge), which possibly occurred by very high charging currents at the beginning of the charging process of their own. In addition, later on. In which vehicle conditions exactly the 12V starter battery is charged via the DC-DC converter from the high-voltage grid, and when not. I made several observations about this and would like to check them against. 1. Question: Does a charging process start at the 12V battery regularly only when the drive readiness has been established? (“Zündstellung 3”, quasi loose, Startknopf with pressed brake pedal) 2. Question: I have observed that the 12V battery during a charging process (here a The 12V battery is not charged. Is this correct? 4. Question: I have a quick loader) with the driving readiness switched on (charging between the circular instruments visibly) but not with the driving readiness switched off (air conditioning and music switched on). Is the observation correct? 3. Question: Observation: Generally with a charging process (DC or AC) with a closed car without the driving readiness the 12V on-board network and the starter battery are not supplied with power. Observes that the 12V battery seems to be charged when you activate the pre-climateization via the app, which also activates the electric heater that hangs on the 400V network. The 400V network of the car is switched on virtually actively and the DC-DC converter is also active. Is that correct? 5. Question: Will the starter battery be charged at some point via the DC-DC converter when the car is standing for long and a voltage drop on the 12V starter battery is detected? 6. Question: Is it known if there is a 12V battery in the car? with the EQS equipment, which leads to problems with too high rest currents, e.g. the Samsung Tablet in the middle armrest back (PAT Fondsitz package Plus with 326 comfort armrest in the rear)? I have not yet so long the vehicle, but got again and again after long service life (hours (long) instead of minutes (short) strange error messages due to self-diagnoses, which warned against problems on the high-voltage grid (“high-voltage system check see operating instructions”). The error messages did not occur after long journeys (>10 minutes) and short service life (<1h). Also never during the journey. The error messages did not occur in the workshop either. After consultation with the workshop it was noticed that it was the standard procedure to directly connect the 12V on-board network in the workshop. To pair an external (stable) power supply so that the 12V battery is spared. Only the desire to remove this coupling and the appearance of the message "The charge state of the battery is low" after approx. 3.5 days of service life, led to a realistic diagnosis that the 12V starter battery has to be weakened and replaced. The battery has been replaced. At the present time everything is fine with a new starter battery - there are no more error messages. 7 . Question: Can the DC-DC converter reach its power limit when a starter battery pulls a huge charge current just before the cell death with a therefore very small internal resistance over the 12V network at the start of the charge? So until due to the power loss in the battery and the associated heating this the internal resistance increases and the charging current falls. Voltage fluctuations in the 12V network would then very probably be the result, which in turn control Is this plausible? Still, I can't rule out that there is still a problem with the consumers at rest, but I notice on short distance that the power consumption (x kWh/100km) on the first 3km of a journey is on average 10kWh/100km lower than before the replacement of the battery, which I think is low. The error messages don't appear at the moment. However, I find it challenging that the ECUs leave wrong errors in the memory, but that a worn out 12V battery does not seem to recognize.... which was also classified in the app as "health condition OK".