cooling fan not working

[ryan319]

i'm really stumped on this. i cannot get my cooling fan to kick on. it doesn't come on when the temp comes up or when i turn the AC on. i've tried troubleshooting on vortexbuicks but i can't seem to figure it out.

i think that i might have a ground problem. is there a way that i can make a new ground connection to see if that fixes it? any other ideas on how to troubleshoot this?

 

[Pronto]

Does it run if you hotwire it? Maybe the motor is burned out.

 

[mikestertwo]

Bypass the low speed resistor and see if it kicks on.

 

[ryan319]

Does it run if you hotwire it? Maybe the motor is burned out.

i pulled the fan out and it if i put power and ground on it with a batter charger and it runs fine. i can also get it to run in the car with every hooked up if i ground the single green wire on the coolant switch. the previous owner put in a hi/low switch and if i ground the pink and black wires from that switch i can get the fan to turn on high and low. there's also a yellow wire that goes to that switch but it doesn't seem to do anything.

i have 12v power at the 2 red wires in the harness and the brown with the key on but nothing is getting to the fan.

could the coolant switch be bad? does that switch control the fan for both temp and when the AC is on? i'm going to try cleaning and changing the relays tomorrow and see what that does. any other ideas?

i'm confused because when i put the car away last fall everything worked fine.

 

[ryan319]

changed the relay and temp sensor and nothing. i couldn't get a coolant switch (the one with a single green wire on the intake). i'm wondering if that's the issue?

how can i test that i have a good ground? i checked the grounds on the passenger head and they all look fine. i gave a little tug on each wire and everything was solid.

 

[aminga]

changed the relay and temp sensor and nothing. i couldn't get a coolant switch (the one with a single green wire on the intake). i'm wondering if that's the issue?

how can i test that i have a good ground? i checked the grounds on the passenger head and they all look fine. i gave a little tug on each wire and everything was solid.

That one's just a failsafe. It will start the fan should the ECM fail to.

You can test your fan by grounding that wire to the intake. if it doesn't come one the fan is probably bad

 

[ryan319]

That one's just a failsafe. It will start the fan should the ECM fail to.

You can test your fan by grounding that wire to the intake. if it doesn't come one the fan is probably bad

if i ground the single green wire on that sensor the fan runs. buy why won't it kick on when the car comes up to temp. i have a TT chip so it should turn on around 165.

 

[ryan319]

just to bring closure, the fan switch wired in by the previous owner was either faulty, or was wired incorrectly. i removed it, rewired everything back to stock, and installed my own manual hi/low switch and now everything works properly. the fan runs off the computer or my switch.

cheers

 

[Pronto]

Glad you got it resolved.