Just picked up at 95 civic recently and as I was pulling out the climate control to replace the broken lever for temp adjustment I found a melted plug that connects to the speed setting. From what It looks like, wires aren't melted but where the dash plug contacts and the internal switch contacts are melted. I broke apart the switch and found that the only part melted are on the contacts of the highest setting (4) both internal and external only at the very ends of the contacts but not in between. I was thinking it might just be bad or loose contacts that might've overheated it? Though the contacts inside didn't looks corroded or off. I was planning on cleaning the contact and replacing the plug and also the speed switch but I'm not sure how safe that is since I'm afraid it might be something more serious. I may be over thinking it but is it also possible the blower or resister might've caused this? The blower resistor looks fine except for what looks like the hard thermal paste is crumbling off the coils. I've already check the fuse and the relay didn't notice anything off. Any suggestions?

 

The blower motor gets voltage via hood fuse #37. What is the amperage rating of the fuse inserted into the #37 slot?

Can you tell whether the blower motor is the original or a replacement?

Yellow connectors are generally used for the airbag (SRS) system. Does the cluster SRS work and stay on steady with engine running?

 

The fuse is 30 amps and it's factory a Denso blower. SRS on the cluster only comes up on startup and goes away with the rest of the other warning lights (cel, batt. etc)

 

The original 25 year-old blower motor?

Have you tested whether the blower motor works?

Replacing the switch and plug is a good idea.

 

I'm not sure if it's the factory original one but I can confirm that it's the same part since 2000 so good chance it is and it does work on all speeds. I'm just going to assume it's just bad contact or contaminated enough from the old grease to cause it to heat as much as it did.
Plan is to replace the switch, plug, and run it on high while keeping an eye on the switch for the next couple days. If it does melt again it probably is the blower since it's so old, I think it would have just enough resistance on top of extended use of the highest speed to melt the switch. I'll update if I find anything new.