Switches & Instrument Panels: Operation

The speedometer on 300SD and 380SEL models is electronic, with a sending unit in the rear of the transmission. All other models use a cable-driven speedometer. The 300SD and 380SEL models also use an electric oil pressure sending unit.

All other models have an oil pressure line to the instrument cluster. Fuel and temperature gauges on all models use variable resistance sending units. Vacuum gauges are connected directly to the intake manifold by a vacuum line.