I have a 95 C280 with 135K miles on it. Brought to me as a no start, meaning it'll crank over for days but will not fire up. Checked the voltage at the lead attached to the first coil, and it was around 0.35V with the key on. MB Shop manual says it should be closer to battery voltage value when key on and ~10V when cranking. Whats interesting is that when I put the key in the ignition and turn to start, the doors will lock and unlock, for reasons i am not sure. Could this be related to the no coil voltage/spark issue? I have a parts C280 of the same year that I have swapped the OVP, coils, ecu, fuel pump relay and a few other random items unrelated. The wiring harness seems to look nice, but not going to rule that out yet. The review mirror doesn't have the leds on it, so to me that says it doesn't have an alarm, and I can't seem to locate the alarm box under passenger foot panel, only found the carb emissions box. If it were an alarm issue, O would think the car wouldn't crank over.. Is there a way to somehow get direct power to the coils for testing to see if I can get it to spark? I would suspect the crank position sensor too, but that shouldn't dictate my coil voltage.
Any experiences had would be great to hear! I'll be posting updates if I find anything wrong myself.