2007 Mercedes SL-Class Owner's Manual - Page 421

Practical hints Jump starting Start the engine of the vehicle with the charged battery and run at idle speed. Connect negative terminals 3 and 4 of the batteries with the black jumper cable. Clamp cable to charged battery 3 first. Start the engine of the disabled vehicle. 1 Positive terminal of charged battery 2 Positive terminal of discharged battery 3 Negative terminal of discharged battery 4 Negative terminal of charged battery Connect positive terminals 1 and 2 of the batteries with the red jumper cable. Clamp cable to charged battery 1 first. You can now turn on the electrical consumers. Do not turn on the lights under any circumstances. Remove the jumper cables first from negative terminals 4 and 3 and then from positive terminals 2 and 1. You can now turn on the lights. Have the battery checked at the nearest Mercedes-Benz Center. Warning! G Keep flames or sparks away from battery. Do not smoke. Observe all safety instructions and precautions when handling automotive batteries ( page 281). The starter battery is located on the right side of the engine compartment. Make sure the two vehicles do not touch. Turn off all electrical consumers. Apply the parking brake ( page 61). Make sure the gear selector lever is set to position P ( page 168). Open the hood ( page 274). Remove the red cover from positive terminal on both vehicles ( page 414). ! Never invert the terminal connections. 420