Use the search mechanism. OVP is probably the single most talked about problem since I have been here.
The device is basically a surge protector for various important/expensive control units. It uses a zener diode to short all voltage over a set point to ground through the fuse.
Jump starting with a battery charger or other high voltage methods takes out the fuse. Alternator/regulator problems can take out the fuse/fuses. But, most problems are actually just defective electronics or circuits within the device. On a wide group of 201/126/124 cars the simultaneous incidence of cold start problems and ABS light are a good clue. I have had units that would power one and not the other controller though and I have seen enough intermittant internal connections to waste weeks searching.
I now replace any OVP with original date code if the car has any stalling or cold starting problems.
Bosch Master, ASE Master, L1
33 years MB technician