- making repeated unsuccessful attempts to start the engine, or leaving the lighting devices on for a long time with the engine off;
- malfunction of the charging system (the alternator drive belt is loose or broken, the electrical wiring is damaged, or the alternator itself is faulty);
- malfunction of the actual battery (the electrolyte level has dropped or the battery has expired).
When starting the engine from an external power source, attention should be paid to observing some special precautions:
- Do not attempt to start the engine with a frozen battery (A discharged battery can freeze even at 0°C) - preheat it; subsequent regular use of a thawed battery is not recommended;
- starting the engine from an auxiliary power source should be carried out only with a cold power unit and catalytic converter;
- do not start using a device for accelerated charging of the battery;
- before connecting the auxiliary battery, make sure that the ignition is switched off;
- use only cables with sufficient cross section (not less than 25 mm2 for a gasoline engine and not less than 35 mm2 - for diesel) and with insulated terminals, cables must comply with DIN72553;
- make sure that all consumers of electricity (lighting and heating devices, windshield wipers, etc.) were also turned off;
- wear protective gloves and goggles;
- make sure that the auxiliary battery has the same output voltage as the battery installed in the affected vehicle;
- if a battery installed in another vehicle is used as an auxiliary power source, make sure that the vehicles do not touch each other;
- the engine of the donor car must be idling;
- make sure the transmission is in neutral;
- from a discharged battery, remove the ventilation covers and cover the holes with a rag.
The scheme and sequence of wire connection is shown in illustration 10a.
10a Sequence of connecting wires for starting the engine from an auxiliary power source
A Dead battery
B Good battery
Connect the end of one wire (usually red) to the positive terminal of the dead battery. Connect the other end of this wire to the positive terminal of the auxiliary battery. On 3.6L models, the positive lead from the auxiliary battery can only be connected at the point shown in illustration 10b. To access it, open the cover in the direction of the arrow.
10b Point to connect the positive wire when starting the engine from the auxiliary power supply
One end of the second wire (usually black) connect to the negative terminal of the auxiliary battery, Connect the other end of the black wire on all models to the body ground point (see illustration 10c). On models with "Start-Stop" connecting the ground wire directly to the negative terminal of a discharged battery is strictly not allowed.
10s Ground wire connection point when starting the engine from the auxiliary power supply
Make sure that the connecting wires do not come into contact with moving components in the engine compartments of both vehicles (fan impeller, drive belts, etc.). In a car with a dead battery, switch off the car phone, or follow the instructions for using the car phone in this case.
While maintaining the vehicle with a healthy battery at 2000 rpm, follow the normal procedure for starting the vehicle with a dead battery, then let it run for at least three minutes at high speed.
Note: Do not allow the starter to run continuously for more than 10 seconds.
In order to prevent voltage surges at the moment of disconnecting the wires, turn on the rear window heating and the climate system fan, then, with the engine running, disconnect the wires, acting in the exact reverse order of their connection (see above). Be sure to install the removed ventilation covers on the battery.