firbird

i have a problem with my cooling fans.. first off they stoped working and noticed my temp around 200 deg and noticed something was wrong and pulled over when it got to 220 (usally runs at 175) and noticed that my fans were not on.. and looked at the fan switch and so on and every thing seemed ok and messed around with it not finding anything and right when i was about to give up i turn teh key and my fans came on and was doing good and i was just like wtf? and was not going to complain right then and there so i drove the rest of the way home and looked over it and looks perfectly fine so i decided i did not want that to happen again and grounded my fan wire and unhooked my switch and it turned on when the ign was turned on and seemed to work good (prolly not a good thing to do anyways) but anyways it seemed good so i was happy for then and went somwere and when i parked my car i noticed my fans did not stop when i took the key out and poped the hood and looked at the wire and every thing then looked the the relay and looked good intill i touched it and burnt me and was somthing around 2000 deg and i eventually was able to unpluge it and the internals were all melted inside and i let it cool and put it back and nothing happend and was unable to get the fans to turn on, and then i went to the part store and picked up a new one and i replaced that and tried it and it just kept on no matter what and i noticed it was getting hot too and yes i took of the ground wire from the switch to bypass it and then i went over to the switch my engine was like at 100 deg or less so it sould not be turned on and when i unpluge it, it turned off and when i pluged it back it turned back on but it was not up to temp yet but that does not explain why the relay is getting so hot to the point were it will melt its self to a big ball of plastic... could a dead fan switch to this? i got some aftermarket one that turns on like at 175 or somthing

Desert86Roc

Bad relays can stick in the "on" position. Change the relay.

Danno

The ONLY reason the relay will get that hot is if you have a bad connection in the part(contacts) that control the fan. These connections or the connector get corroded or just deteriorate and develop resistance causing extreme heating of the contacts. Take a look at the connector after you unplug the relay. If it looks burnt or discolored you will need to replace the connector. If the fan is drawing excessive current it will blow the fan fuse, if the relay is hot and the fuse does not fail it is resistance at the relay connector. This is a very common problem in auto electrical systems because the voltage is so low to run things like motors, etc. That is why there is talk of going to a 48 volt auto electrical system.