*HELP* cooling fan wont come on

[tntcorvette]

The cooling fan on my '85 will not operate. I ran power directly to the fan and it began to run so I have eliminated the fan motor. I checked the fuseable link (20amp) and its fine. I checked the relay and I ran a ground to a few of the terminals and it clicked.

When I connect the alcl links a&b together with the ignition on the fan does not operate but it sounds like my iac is working???????

How do I test for a bad relay?

HELP!!!!!!!!!!!!!

 

[nyernga]

The cooling fan on my '85 will not operate. I ran power directly to the fan and it began to run so I have eliminated the fan motor. I checked the fuseable link (20amp) and its fine. I checked the relay and I ran a ground to a few of the terminals and it clicked.

When I connect the alcl links a&b together with the ignition on the fan does not operate but it sounds like my iac is working???????

How do I test for a bad relay?

HELP!!!!!!!!!!!!!

The wiring diagram for my 88 shows a 3 amp fuse as well as a fusible link. Have you checked that yet?

Len

 

[c4cruiser]

IIRC, fan relays are not that expensive and I think the fan relay is the even same one as the fuel pump relay. From what you described for troubleshooting, I would think that the relay has gone south. The fan should have started when you grounded pins A and B in the ALDL.The ECM grounds the relay when it gets a specific value from the coolant temp sensor and that starts the fan.

 

[Vettelt193]

if you ran power right to it and it worked, run power to it with the relay in place... meaning, jump it manually from the wiring going into the relay. if nothing works then, relay is shot.


If it were me, I would spend the $$ on the new relay and just try it. they really aren't expensive, and easy to change, and they are known for going bad.

 

[68Roadster]

Try tapping the relay with a screwdriver, some times the points stick. Also just removing it and putting it back in works, cleans the contacts.
If the relay doesn't do the trick, I would go for the coolant sensor next.

 

[tntcorvette]

guess when I ran power to hte fan directly from the battery it burnt out the fan. I got a new relay and there is power on & off via hte ignition on with the alcl jumped and + and ground to the fan connector.

I got a new fan and the fan comes on!

 

[BlackNBlue95]

Try swaping the relay with another one and for the ADL ground deal and see if they come on or just jumper the relay. Just a tech tip, if a relay clicks it could still not have continuity through the switched side of the relay.
-=Rick

 

[Agent 86]

http://members.shaw.ca/corvette86/Cooling%20Fan%20Control.pdf

 

[femurphy77]

If you haven't already found a solution. . . . . .

My '92 was doing the same thing. There is a fuse labeled "Gauges" that feeds the fans. The fuse was good but there was some corrosion on the blades of the fuse. I replaced the fuse and all is good. Like I said, this is related to a '92, yours may be different. FM, Indy