Radiatior fans not turning on

[ohlegend]

I am trying to get my car to stay idling, I melted high temp paint off of cylinders 1 & 4. The radiator fans never turned on. How do I check to see if I have bad fans?

 

[952g63t]

I just went through this mess a couple weeks ago. Turned out my temp sensor was not making complete contact inside the connector clip. Might be a good reference though to trouble shoot.

http://www.dsmtuners.com/forums/mai...nly-coming-when-i-disconnect-temp-sensor.html

Good luck.

 

[young97 gst]

is there a fuse for that?

 

[spyderdrifter]

First, get 2 jumper wires and attach them to the positive and negative terminals on the fan connector. Then take the other sides of the jumper leads and connect the positive to a battery, and touch the negative to the negative post. If the fan kicks on, your fan is fine. I don't believe your fans are bad. Have you done any recent work involving the coolant system? If so, make sure the system was properly burped. If your ECT sensor is bad, that too can keep your fans from kicking on. Likewise, a bad thermostat can have a similar affect. So you have a few possibilities to check out.


There are fan relays, but don't think there's a fuse.

 

[luv2rallye]

+1. I agree. First make sure your coolant is full and burbed. Then test your 2 wire coolant temp sensor (CTS): http://www.dsmtuners.com/forums/mai...couple-minutes-after-start.html#post152374418. The ECU controls the fans on a 2g. Also make sure the "Rad Fan" 30A fuse is good in the engine fusebox.

 

[ohlegend]

How long (usually) does it take for the fans to turn on?
I had it idling for 2 mins (while revving it). The High heat VHT paint flacked of my header (Cylinders 1 and 4)

 

[ohlegend]

could bad temp sensors cause this too?

 

[spyderdrifter]

A bad temp sensor (ect sensor) can trigger many symptoms of other problems. If you think it's bad, test it first to confirm.

 

[ohlegend]

I replaced the temp sensor and tested the fans. All works well. I replaced some relays to see if that fixes the problem. I'm also changing the other temp sensor tonight.

*both fans work if I connect them to the battery. They still don't work on their own

 

[ohlegend]

Still the same issue, I replaced both temp sensors and tried unplugging the 2 wire connector. They turned on when it was unplugged. So is the connector bad on the temp sensor?

 

[952g63t]

If you are certain your engine reached operating temperature before you unplugged the cts, than it is possible there is a short in the connection somewhere.

 

[spyderdrifter]

If you have a way to have your radiator cap pressure tested, do it. A few months ago when I swapped my aluminum rad back in, my fans wouldn't turn on after allowing it to burp for 45 minutes. I put the cap on afterward and still no fans. Tested the cap and it wouldn't even hold 1psi. Bought a new one following that and ran the car. maybe 5 minutes later the fans turned on. Thus showing me how much a cap will affect the cooling system with age.

I would also de-pin the connector and check the wires and pins for corrosion and damage.

 

[ohlegend]

Coolant temp never got hot enough to kick it on.