If it’s anything like my bay (except mine has breakers, not fuses), the windshield brow was cracked and leaked rainwater that ran down the inside of the driver’s “post”, through the cable loom hole, and into the electric bay. It would not have a way out, pool an inch deep, and would go undetected sometimes for weeks parked here at home. When discovered, I’d have to use a big sponge to sop out the water. Then I’d keep desiccant tubs in there just in case.
The moisture in there rusted some screws that hold components to the white mounting board (melamine), and caused swelling and cracking of the board itself around its own mounting screws. Fortunately a member here, Ed Buker, recommended Corrosion-X, so after I thoroughly Lexeled the cracks in the brow rubber and stopped the water ingress, I used that product on metal parts throughout the bay to prevent further deterioration. Nary a drop of water has entered the bay for at least 8 years, and desiccant has no longer been necessary. I also found a smidgen of green on a couple pins inside the large cylindrical connectors in there, so I cleaned them and added dielectric grease before reassembling.
The reputation for leaking through nano-cracked clearance light lenses over a windshield could also result in water getting in similarly. As related over time on this Forum, many owners find water in the dash area from that. Like a leaky house roof, water can display strange, variable, and well- concealed routes downhill.
Joel
