What phrase is correct when jump starting a car? The phrase "positive to positive, negative to ground" is correct when jump starting a car. Do you need a jump lead to jump start a car? The RAC do not recommend bump starting a vehicle, please follow the advice in the How to jump start a car with jump leads or How to jump start a car with a portable battery pack sections. Can you jump start a car with a flat battery? The most common and effective means of getting your car going with a flat battery is by using...