Originally Posted by
ala_xfire
As far as I know, the reason for removing the negative cable first is the wrench.
No harm if the wrench touches the frame from the negative terminal before it is loose,
can't say the same for a bridge from the positive terminal to the frame.
Possible exploded battery or severe burns from the hot wrench
That is one of the main reasons for removing the NEG cable first (reverse if you have a POS ground vehicle, if there are any on the road anymore). It becomes a necessity on our XF's due to the alarm system because the alarm will sound if the POS is removed first.
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