Safety Fuel Shutoff

WARNING: This page is about a different car, the 1992 Mercedes-Benz 400E. However, it is still accessible from the selected car via links, so may be relevant.

For safety reasons the LH control unit is connected to the switch contacts in electronic accelerator actuator or cruise control/idle speed control actuator through a separate wire. With engine at idle or while driving, the switch contacts send a positive signal to the LH control unit.

If throttle valve opens more than the position specified by accelerator pedal and cruise control is not engaged, a safety contact in the electronic accelerator actuator or cruise control/idle speed control actuator sends a ground signal through the electronic accelerator module or cruise control/idle speed control module to the LH control unit. This will turn off fuel injectors. Fuel injectors will only be turned on after engine speed drops to less than 1100 RPM. If malfunction continues, engine can only be operated at speeds up to 1100 RPM.