A-Class Interactive Owner's Manual [In depth | Practical advice

Jump-starting

If your vehicle's battery is discharged, the engine can be jump-started from another vehicle or from an external battery using jump leads.

Observe the following points:

Jump-starting may only be performed when the engine and catalytic converter are cold.
Do not start the engine if the battery has frozen. Thaw the battery out first.
Jump-starting may only be performed from batteries with a nominal voltage of 12V.
Only use jump leads which are protected against polarity reversal and which have a sufficient cross-section and insulated terminal clamps.


Jump leads which are protected against polarity reversal and further information about jump-starting can be obtained from any Mercedes-Benz Service Centre.

Avoid repeated and lengthy starting attempts.

Never start the vehicle using a rapid battery charger.

	Risk of injury
There is a risk of acid burns when jump-starting a vehicle due to the gases which escape from the battery. Do not lean over the battery while the engine is being jump-started.

Risk of explosion

Gases escaping from the battery during jump-starting may cause minor explosions. Avoid creating sparks. Keep naked flames away from the battery, and do not smoke.

Comply with safety precautions and take protective measures when handling batteries. You will find these under "Battery" in the index.

	Make sure that the two vehicles do not touch.
	Apply the handbrake.

	Manual transmission: engage neutral.
	*AUTOTRONIC:** move the selector lever to P.
	All vehicles: switch off all electric consumers.

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Positive terminal of donor battery

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Positive terminal on your vehicle

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Negative terminal of donor battery

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Negative terminal on your vehicle

	Open the battery cover more.
	Connect positive terminal on your vehicle to positive terminal of the donor battery using the jump lead, connecting the jump lead to your own battery first.
	Start the engine of the donor vehicle and run it at idling speed.
	Connect negative terminal of the donor battery to earth point of your vehicle using the jump lead, connecting the jump lead to the donor battery first.
	Start the engine.
	Electrical consumers can be switched on again. Do not switch the lights on however, as this will overload the battery.
	Remove the jump lead from earth point and negative terminal first, then from positive terminals and , each time disconnecting from the battery on your own vehicle first.
	Have the battery checked at a qualified specialist workshop, e.g. a Mercedes-Benz Service Centre.