The OVP sacrifices itself when voltage exceeds acceptable levels in the system. At a certain point, it will self-destruct if it cannot protect the system within its electrical specifications.

If this were me, the first thing I'd do, when it dies, is to try reseating the OVP and see if that matters (unplugging it and plugging it back-in)-- I think on your car (?) the OVP is easy enough to get to.

The other thing I'd do is make darn sure that any "bad OVP" is fully verified to be bad. You should disassemble the OVP's and see if you can see any visual burning/damage. I'd basically be asking myself if the act of reseating the OVP (taking it out and putting one back in, maybe even the original one) actually solves the problem.

If reseating the OVP solves the problem, this leads to a few possible conclusions:

1) The OVP connector (including connection to the harness) may have a failure in it.

2) There is a grounding problem for the OVP connector and/or the harness to which the OVP is connected.

In the event the OVP is actually failing, I'd also go to the same two conclusions above, therefore agreeing with Arthur in one case that the ground can be a problem. In such a case, I think (???? I do not necessarily know what I'm talking about here, I have not looked at your car, connectors, harness) one thing to do would be to attempt to reground your OVP connector to a local ground in the car (a good solid part on the body) thereby no longer making use of the ground running to your OVP. If this is a bad idea for some reason (I can't think of it, there is only one ground in a car and you need it wherever you are even at the OVP) then someone can comment.