I have taken apart and repaired 2 OVP relays. You will need to use a small screwdriver to VERY CAREFULLY pry the aluminum housing away from the base of the relay. This can be done without tearing the aluminum, but patience is your friend.

Once the outer housing is off, you will want to visually inspect the riveted connections at the base of the relay. Chances are good that corrosion has set in, and one or more of the pins is making an intermittent connection.

Clean the connections well, then break out a good strong soldering iron to repair the joint. Yes, it's a pain, but OVP relays aren't cheap.

I keep a back-up OVP in the spare parts box in my trunk.

Steve.

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