190e fuel pump relay and OVP
If you're asking, are they two seperate relays, the answer is yes.
The OVP and Fuel Pump Relay on my 1986 190E are located behind a plastic shield behind the batery.
I believe that the OVP is there to protect the Fuel Pump relay from excessive voltage.
Make sure that you verify weather or not you have voltage at the fuel pump when you turn the ignition. Also of note on my car when trying to determine my problem, is that on the Fuel Pump the negitive cable is Red and positive is Black. This caused me some confusion and lead me to believe that I also had a relay problem.
Start with voltage at the pump when the car stalls and then go to the relay.