no voltage at a,b post in fuse box, w123
 

When I'm driving, or when I turn the key to position 2 (just before going all the way), there is no voltage at the post between the a and b fuses at the far left of the fuse box. None of the windows work, neither does the turn signal. If I jump directly from the + terminal on the battery to that post, things work again.

Also, every now and then (rarely) for a split second, power will come back to it. When this happens there's a clicking sound that seems to be behind the climate control panel (but I'm not sure).

Has anyone had a similar problem? My hazard switch has been flakey for years; I initially thought this might be the problem, because this problem seemed to manifest as I was driving and toggling the hazard switch to get the turn signal to work again.

Is there a wire that sends to that post in the fuse box from somewhere behind the radio or climate panel?

Thanks.