WARNING 
Improper use of jumper cables when jump-starting a vehicle 
with a dead battery can cause the battery to explode, leading to 
serious personal injury. To help reduce the risk of battery ex-
plosion: 
  All work on the batteries or the electrical system in your ve-
hicle can cause serious acid burns, fires, or electrical shocks. 
Always read and heed the following WARNINGS and safety pre-
cautions before working on the batteries or the electrical sys-
tem ⇒  Vehicle battery. 
  Always make sure that the battery providing starting assis-
tance (the booster battery) has the same voltage as the dead 
battery (12 V) and about the same amperage capacity (see bat-
tery label). 
  Never jump-start a vehicle with a thawed or frozen vehicle 
battery. The battery can explode. A dead battery can freeze at 
temperatures around +32 °F (0 °C). 
  A battery that is frozen or was frozen, but has since thawed, 
must be replaced. 
  When the vehicle battery is jump-started, it gives off hydro-
gen gas, which is highly explosive! Always keep fire, sparks, 
open flame, and smoking materials far away from vehicle bat-
teries. Never use a mobile telephone while connecting or dis-
connecting jumper cables. 
  Jump-start batteries only in well-ventilated areas. Batteries 
give off highly explosive hydrogen gas during jump-starting. 
  Always route the jumper cables so that they cannot get 
caught in any moving parts in the engine compartment. 
  Never short out the battery terminals by connecting the posi-
tive (+) and negative (-) terminals with each other. 
  Never connect the negative cable from the other vehicle di-
rectly to the negative terminal of the dead battery, as this may 
cause the hydrogen gas given off by the dead battery to ex-
plode. 
  Never attach the negative cable from the vehicle providing 
starting assistance to any part of the fuel system or to the 
brake hoses or brake lines.