17 Wintersells Road Byfleet Surrey KT14 7LF
Jump starting cars with flat a battery
Jump Starting Your Car
The correct sequence of connection and disconnection is set out below.
However, if you are in the slightest way unsure, do not take the risk.
Recommended Jump Start Procedure
Warning: Jump starting can damage your vehicle electronics.
Check the vehicle operating manual. If there are no specific instructions, then follow the steps below. If the failed battery is open circuit*, then do not attempt to jump start. If your vehicle is fitted with electronic components, ensure that a set of surge protected jumper leads are to be used.
*Open circuit batteries can be detected by:
Step 3—Negative Earth Vehicles Only
Connect the vehicles in the following exact sequence. Make sure the jumper leads are clear of any moving parts.
Start the donor vehicle (with the good battery), then start the vehicle with the flat battery.
After starting, allow both engines to idle for about five to eight minutes before disconnecting the jumper leads (to allow both cars’ electrical systems to balance). This reduces the possibility of damage to vehicle electronics.
Then turn both car engines off.
Then start the car with the flat battery to make sure it has accepted a charge.
After your vehicle has been jump started, providing the battery is serviceable, it will only have a surface charge. This surface charge may successfully continue to operate the vehicle for the rest of the day, but may well dissipate overnight, presenting another flat battery the following morning.
It is recommended that the battery be fully recharged by using a battery charger at the earliest opportunity.