2010 S63 Startup/battery/electrical issue
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2010 S63
2010 S63 Startup/battery/electrical issue
I have a 2010 S63 that I have owned for a bit over 5 years and it has about 86K miles on it. This fall, I started having an issue where when the temperature would get below freezing (overnight), I would have a no start/no crank condition and would sometimes get a variety of error messages on the dash. If I disconnect the negative terminal on the battery for a minute or so and then reconnect, the car starts just fine with no check engine light or computer errors. Thinking it may be a battery issue, I replaced the battery, thinking that it was definitely a battery issue because the no start/no crank issue only happens when the temp goes below freezing. I have been getting my batteries (AGM) from Costco and have never had any issues. However, thinking that it could be an engineering/manufacturing issue with the battery, I got another battery (duracell AGM) but STILL have the issue. I have also replaced both starter relays as well.
So it is not a battery issue but a cold temperature is causing the no start/no crank issue that is only resolved with disconnecting/reconnecting the battery. The cold temps seem to be causing some kind of voltage fluctuation that is maybe affecting the ECU? I have verified that the battery voltage is not dropping significantly when this happens...If I connect a scan tool before the battery disconnect/reconnect, I am getting faults in nearly every module. However, after the disconnect/reconnect, no faults at all or check engine light.
Anyone seen this before or have any suggestions?
So it is not a battery issue but a cold temperature is causing the no start/no crank issue that is only resolved with disconnecting/reconnecting the battery. The cold temps seem to be causing some kind of voltage fluctuation that is maybe affecting the ECU? I have verified that the battery voltage is not dropping significantly when this happens...If I connect a scan tool before the battery disconnect/reconnect, I am getting faults in nearly every module. However, after the disconnect/reconnect, no faults at all or check engine light.
Anyone seen this before or have any suggestions?
