When you change out a battery (especially as cars get more and more reliant on computers) do yourself a favour and get yourself two sets of jumper leads. Connect the new battery to the terminal connectors with one set before removing the terminal connectors from the old battery. then put the new battery in place. Connect the old battery to the other jumper leads prior to removing them from the new battery. Then connect the terminal connectors to the terminals on the new battery before removing all the jumper leads. This keeps power to the circuitry at all times and prevents any "issues"

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2004 E53 4.4L N62