there is no EDS connector to speak on on the E300D, the wiring to the ELR cube is power, ground, tach, ELR control, coolant sensor.

The ELR unit is powered from the overvoltage relay output, if you see your tacho quitting and the rpm going to a shaky 500 rpm then your ELR cube is switching off (bad OVP)

At this same moment your A/C compressor will also quit working.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)