Hawkman978

My car is the 3.4L V6, and its fan will not turn on. I have changed the thermostat, replaced radiator fluid. But when I turn on the AC in my car the fan still won't start. The car will warm up and not stop heating up causing the engine to over heat. I have also checked the oil at running temp. Doesn't appear to be a blown head gasket. I have also checked the switch next to the thermostat and it appears to be working. been trying to fix for three months now at a total loss. Any advice will help.

Injuneer

You can't really tell if the coolant temp sensor (it's not a "switch") is working by looking at it. If it is seriously defective, open or shorted circuit, you will get trouble codes DTC 14 or 15. Have you scanned the PCM for codes?

If the sensor is simply inaccurate, use this to test the sensor, and the wiring to it:

4th Gen LT1 F-body Tech Articles

The fan is turned on when the PCM sends a ground to the cooling fan relay in the underhood fuse box. The relay is provided with 12V power via fuse #6 in the underhood box. Check that fuse. Verify that (key on) there is 12V at the brown wire on the cooling fan relay.

The fan gets 12V power directly from the battery "+" box, via a "fusible link". It's possible the fusible link is blown. Go to the fan relay. Measure the voltage at the terminal with the red wire attached (key does no have to be on, power is always supplied). If you have 12V at the red wire, move to the fan connector, and measure the resistance between a chassis ground and the black wire in the connector (connector off fan). Should be close to 0 V.

This is what the fusible links look like:

Courtesy of Shoebox

http://shbox.com/1/fusible.jpg

Injuneer

Now I find I've already answered this question once before, a few days ago. If you didn't feel my answer was adequate, or you didn't understand something, all you had to do was add on to that thread.

Starting a new thread when you have already received responses on an earlier thread on the same subject is not a good idea, and wastes the time of people who are trying to help you.

https://www.camaroz28.com/forums/gen...urning-883771/

Fred/MODERATOR

Hawkman978

I had accidentally left out the size of the engine and what you posted was for the wrong size engine, therefore the information was not correct. I apologise for the inconvenience.