Last week the coolant fan started to work when i turned the ignition on, then it stopped working after a while.
yesterday i took out the vette and the fan just didnt work at all, i realized that when i saw the temp at 230f and the fan wasn't working at all after a few seconds the aux fan started.

Could it be a faulty relay?
Where is the coolant fan relay located?

1989 coupe auto

One of the other fellas with an 89 will come to the rescue here shortly. Have you checked for voltage at the fan first. Just to be sure the fan motor hasn't taken a dump. If the fan still works then we can back track to the relay. On my 94 the relays are on the left side of the fan shroud.

Hopefully someone will come by soon. Its not good weather to be without the fan!!

It does sound like the relay, the easiest thing to do is swap the relays and see if the main fan will power up when the temp gets up.

Hopefully someone here can get you the location (I don't have a 89 FSM), but, both relays on a LT1 (92) are on the radiator shroud, drivers side. The swap is easy.

You can also find the ground wire in the harness (again, you need the FSM diagram). You may be able to backprobe the relay connector with a ground wire to see if that turns on the fan. The relays are turned by grounding them.

According to "Haynes", '88 and later relays are left of radiator shroud, (earlier models on fender under master cyl.)
Fusible link is behind battery, temp. switch is behind dipstick on cyl. head.
Does the fan come on when you turn on the A/C? If so, it would take the relay/fan motor out of the equation.
The fan came on when you turned the ignition on? Why? Was the motor hot? Was the ALDL jumped?
The FSM is a wise investment.

For the 89 the main fan relay should be on the rear of the driver's side fender well. The auxillary relay is mounted to the radiator shroud. I think those are right off the top of my head. Fuel pump relay is mounted to the firewall next to the brake booster for sure.

If not sure which is which just pop a new relay in each location and see if it works.

As Joe mentioned, does the fan turn on when you jumper a&b on the aldl? If so the wiring and motor should be ok.

Matthew

Thanks for the replies gurus, i will try jumping the aldl to see if the fan comes on will report back what i find

Hi gurus, i fixed the problem, i tried the aldl trick and sure enough the fan didn't work.
So i swapped the relay from the main fan to the aux one and it worked like it is suppose to work.