Function of the injection system: - ra07206020010x(0010)

WARNING: This page does not describe the selected car, but rather 42 other vehicles, including the 1999 Mercedes-Benz S600, 1999 Mercedes-Benz S500, 1999 Mercedes-Benz S420, 1999 Mercedes-Benz S320, and 1999 Mercedes-Benz CL600. However, it is still accessible from the selected car via links, so may be relevant.

T. Vacuum engine stop with car key (glow-start switch) - Engine 602.96, 603.96/97 TURBO (Model 463.3: pay attention to deviations)

T. Vacuum engine stop with car key (glow start switch)

Models 124, 126, 201
The vacuum for the key-operated engine stop is supplied by the check valve (140) of the main vacuum line.

Fig 1: Identifying Check Valve
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Fig 2: Vacuum Line Routing Diagram
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Vacuum line routing
Model 140, engine 603.971 model year 1992

The key-operated engine stop is no longer actuated via the glow start switch valve (61c) but via an electric switchover valve (Y9/1) and via a relay (N17/3), which at the same time also switches off the fuel.

Fig 3: Vacuum line routing Diagram

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Vacuum line routing

Key-operated engine stop relay (N17/3), key-operated engine stop switchover valve (Y9/1)

The key-operated engine stop relay (N17/3) is actuated for about 3 seconds after the engine is switched off and operates the key-operated engine stop switchover valve (Y9/1).

Fig 4: Identifying Key-Operated Engine Stop Relay

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

A vacuum of about 500 mbar exists at the key-operated engine stop switchover valve (Y9/1). After this valve is actuated, the vacuum which exists at the valve operates the stop unit at the injection pump pneumatically and moves the control rod into the stop position.

Fig 5: Identifying Key-Operated Engine Stop Switchover Valve

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.