Mercedes-Benz Actuator Locations
Located at the front of the engine, the actuator is very easy to access and test. The connector is indicated by the smaller red circle.
W126 300SDL (OM603) / W124 300D (OM603)
Located under the intake manifold, on the drivers side of the engine. Connector is on the driver's side fender. Both are circled in red
W126 420SEL / 560SEL
Located at the front passenger side of the engine. Connector is mounted to the base of the coolant bottle bracket.
Located at front passenger side of engine. Connector is mounted adjacent to the passenger headlight.
W123 300TD / 300D / 240D
Actuator is located at the front of the engine, driver's side. Connector is located on the driver's side fender. Photos are from PeachParts forum member neumann's 1985 300TD. Locations are probably applicable to the 300D and 240D as well.
The R129 500SL's actuator is located in the front of the engine just next to the power steering reservoir.
W124 300D 2.5 Turbo (OM602)
The acuator is attached to the intake manifold. The actuator in this picture has been painted black. The connector is located on the driver's side fender.