Bought used 1997 mazda 626. Initial symptoms. Parking lights not working. Relay tests out ok. 15A fuse is good. After putting the fuse back in lights started working. Noticed signs of corrosion in fuse box where the fuse sits. couple of days later. parking lights not working again. check fuse and it had melted. even the blue plastic coating on one end of the terminal. Think the terminal or fuse box needs replacing. have any suggestions?
When a lot of current passes through a bad connection that has added resistance to the circuit it creates a voltage drop across that resistance and that causes the connection to heat up. You saw the results.
You can replace the fuse panel but you can also purchase a new single fuse holder with pigtails on each end and solder it to the back side of the bad fuse slot. It will save you a lot over replacing the whole panel.
The problem is where the metal tab of the fuse makes contact with a metal spring in the socket. The corrosion causes high resistance. The resistance combined with current flow generates heat. If you look down in the socket the fuse goes in you’ll see some melting there too. The resistance of a poor contact typically goes up with temperature, so there’s a viscous circle until the resistance gets high enough to cut the flow.
There are probably other corroded sockets in this fuse box, so I would look for a clean one at the junk yards.
That is what i am thinking to. my biggest problem is how to remove the fuse box. the repair manual i have has no info on how the fuse box is installed or how to safely remove it. I am debating between replacing just that terminal or going and getting a used fused box from a upull place.
There’s probably just a couple of 8mm bolts to remove to detach the fuse box. Once it’s floating you can see how it’s made in the back. It might be possible to just replace the one socket. There might even be an unused socket on the fuse box.