89 Cooling fan Will not Stop?
Thread Starter
Cruising
Joined: Apr 2004
Posts: 10
Likes: 0
From: miami lakes florida
89 Cooling fan Will not Stop?
Took the cooling fan relay out--still runs .
Took coolant temp sensor off--still runs
Ignition off vat 12 --still runs
Neg terminal removed from Battery--Stops LOL
Any thoughts---Haynes says bad relay---this will be my 3rd relay---but the previous situations were at high temp--with the relay itself un-plugged and sitting on the ground the fan is still running.
Thanks for all the help in the past but this is new do do ----
Took coolant temp sensor off--still runs
Ignition off vat 12 --still runs
Neg terminal removed from Battery--Stops LOL
Any thoughts---Haynes says bad relay---this will be my 3rd relay---but the previous situations were at high temp--with the relay itself un-plugged and sitting on the ground the fan is still running.
Thanks for all the help in the past but this is new do do ----
Team Owner
Joined: Jan 2003
Posts: 20,326
Likes: 252
From: Summerland B.C. Canada
If the relay is removed it should not run. There are two relays, one for main fan (engine side) and one for aux fan. Are you removing the correct relay ? Has a previous owner direct wired the fan to come on with ign.?
Here is some better info than haynes
http://members.shaw.ca/corvette86/Co...%20Control.pdf
Here is some better info than haynes
http://members.shaw.ca/corvette86/Co...%20Control.pdf
Melting Slicks
Joined: May 2004
Posts: 2,524
Likes: 10
From: Lufkin Texas
St. Jude Donor '05-'06
Originally Posted by solon13
Took the cooling fan relay out--still runs .
--with the relay itself un-plugged and sitting on the ground the fan is still running.
--with the relay itself un-plugged and sitting on the ground the fan is still running.
Without the relay in the harness the larger solid red wire that comes from fusible link at battery power distribution with constant 12 volts on it that goes to terminal E would have to be making direct contact with the black and red wire at terminal A that goes to fan. The fans are independently grounded. The relay just serves as a safe holder of the power and waits for an ECM ground command that is prompted by various sensors. The grounding of terminal F by the ECM switches the power waiting at terminal E to terminal A therefore activating the already grounded fan.
I think you need to thoroughly examine the harness that the fan relay plugs into inside for damage and contacts between wires that I described at terminals E and A. You have to look inside relay itself for the correct terminal letters as the chart on top of relay is misleading.
I hope this makes sense.
Last edited by skateparkdave; Apr 26, 2005 at 03:09 PM.
