My ASD warning light (300E ' 87) is on all the time, it suddenly came during driving. I have tested the following:
Front wheel ABS-sensors is reading approx.: 20 kOhm. Diffential sensor approx.: 7 Ohm. All measured when car is parked.
I have checked the overvoltage relay and secured voltage (klemme: 87E, 87L) is 13.8 Volt on the socket of the ASD-ECU. I have one strange voltage of approx.: 8 Vdc at one of the pins in the ASD-ECU wireing-socket. All this is measured in idlespeed-mode with the ASD-ECU dismounted.
Can you help me coming further in the fault finding proces. If anyone have a wiring diagram (or timing diagram) for the ASD connections I would be very happy, then please mail me directly.