How I fixed a Dell Laptop that refused to charge the battery and recognize that I was using a genuine Dell DC Power adapter. It took some careful adjustments to the DC jack in the back of the laptop. In addition there is a signal cable that easily gets severed over time in the end of the DC power cable. By making these two repairs, the laptop works perfectly, the power cord stays in firmly, and the battery charges without problem.
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How to repair a Dell Laptop / Battery Charging power problem with a DC adapter.