Burnt out relay

[mercman300]

New to this forum and just want to thank all who read and provide answers.

I have a 90 300e. Recently I have been blowing the #7 16A fuse which controls all the heater/AC functions and a good # of engine cooling items as well. On the last blown fuse I went ahead an replaced it and to my surprise I promptly smelled smoke. Looked under the hood and there was a small fire at a relay for the aux pump to the heater core.

This pump connects on one end to the thermo housing and the other to somewhere behind the firewall, presumably to the heater core. Its the relay that I want to replace, BUT.....can I.

MB wants to troubleshoot and find where the short it that caused this dilemma, but I figure the relay went bad and caused it to go, so a replacement hopefully will be the fix. I did go through all the threads for blown fuses(found alot similar, but none exactly like my problem) so I am asking for your help.

BTW-AC still works fine and heat too, so the aux pump is not critical to getting heat to where it needs to go, but I don t want to fool around and catch a 'cold' this winter.

Look forward to comments.

Sam
Paoli, PA

[mercman300]

bump back to top,

need help guys input appreciated.

Sam
Paoli