- Be sure that both batteries are of the same polarity (have the same terminal,
in most cases NEGATIVE grounded).
- Be sure that the vehicles are not touching or a short could occur.
- On non-sealed batteries, be sure the vent cap holes are not obstructed.
- Do not smoke or allow sparks anywhere near the batteries.
- In cold weather, make sure the battery electrolyte is not frozen. This
can occur more readily in a battery that has been in a state of discharge.
- Do not allow electrolyte to contact your skin or clothing.