How to Jump Start a Car Safely (And When to Call a Pro)

A dead battery is one of the most common roadside problems, and jump starting a car is simple once you know the right order. Here's how to do it safely — and when it's better to call for help instead.

What You'll Need

• A set of jumper cables or a portable jump starter pack
• A working vehicle to use as the power source (if using cables)
• Both vehicles parked close enough for the cables to reach, but not touching

Step-by-Step: Jump Starting With Another Car

• Turn off both vehicles and set parking brakes
• Connect one red clamp to the positive (+) terminal of the dead battery
• Connect the other red clamp to the positive (+) terminal of the working battery
• Connect one black clamp to the negative (−) terminal of the working battery
• Connect the final black clamp to an unpainted metal surface on the dead car's engine block — not the battery itself
• Start the working vehicle and let it run for a few minutes
• Try starting the dead vehicle
• Once it starts, remove the clamps in reverse order

Safety Tips

• Never let the red and black clamps touch each other while connected
• Keep sparks and flames away from the battery — batteries can vent flammable gas
• Wear eye protection if you have it, especially with older batteries
• If a battery looks swollen, cracked, or is leaking, don't attempt a jump — call a professional

When to Call a Professional Instead

Some situations are safer left to a technician with the right equipment:

• You don't have jumper cables or a second vehicle available
• The battery won't hold a charge even after a successful jump
• The battery shows visible damage, corrosion, or swelling
• Your vehicle has a hybrid or electric drivetrain with a different jump procedure

If a jump start doesn't work or you'd rather not do it yourself, Citywide Towing Services offers 24/7 jump start service across Houston, with an honest assessment if the issue turns out to be more than just the battery.