Engines Starting Precautions, All Engines Mercedes-Benz WARNING NOTE: Before doing these steps, do the steps in "Pre-Start." Do not use any starting aid, such as ether, in en- gines with an intake air preheater. This could cause an explosion and serious personal injury or death. CAUTION CAUTION Never attempt to start any Mercedes-Benz elec- tronic engine using ether or any other starting fluid. Serious engine damage could result. 1. Turn the ignition switch to the on position ( Fig. 4.1 ). All the electronic gauges on the ICU (in- strumentation control unit) complete a full sweep of their dials, the warning and indicator lights light up, and the buzzer sounds for three seconds.
Don’t crank the engine for more than 30 seconds at a time. Wait two minutes after each try to allow the starter to cool. Failure to do so could cause starter damage. NOTE: Some starters are equipped with optional overcrank protection. If overcranking occurs, a thermostat breaks the electrical circuit to the starter motor until the motor has cooled. IMPORTANT: On vehicles equipped with an intake air preheater, the amber INTAKE HEATER indica- tor stays on for a minimum of two seconds, re- gardless of coolant temperature. Wait until the IN- TAKE HEATER indicator goes out before attempting to start the engine.
CAUTION Protect the turbocharger during the start-up by not opening the throttle or accelerating the engine above 1000 rpm until minimum engine idle oil pres- sure registers on the gauge. 2. Turn the ignition switch to the start position. Without touching the throttle pedal, start the engine. 3. Idle the engine for one to three minutes at 700 rpm (600 rpm for 6-cylinder engines) before operating the engine under load. 4.2