clutch fan on 2005 trailblazer 4.2?

Since your car has an electric clutch it won't work unless it gets power to it. Check fuses and the relay but if the system gets incorrect readings from a faulty temp sensor it may not engage.

Sometimes the fan will run for a few minutes then shut off which indicates to me that the fuse must be ok. I didn't have a problem with it until my power steering line blew out. I'm starting to wonder if the fluid got into a connection and is causing a short etc. I sprayed out the one large connector to the right of the alternator with some electrical cleaner but was giving it a couple days to dry before trying to start it. I don't know if the temp gage was working prior to this problem as I just bought the vehicle recently. The temp gage is not stuck on zero but close to the 1/4 mark. This makes me wonder if the system thinks it is not hot so it does not kick the fan on. As I said I replaced the temp sensor.

Perhaps you need a new thermostat. I would also try purging air out of the system. If the car is not overheating and you have good heat inside the car there is probably nothing wrong. Cold weather is here so your cooling fan will not be running very much if at all.

I do have a check engine light on code P0526 which says fan speed sensor circuit (most likely cause wiring harness). Again I'm wondering if power steering fluid got into something. The thermostat seems like it is working fine. I've had problems with them years ago on other vehicles so I'm kind of ruling that out. I find it curious that the gage is not just at zero. It seems to me that it would return all the way back down if it was not getting any signal or after the vehicle cools down. Also, after installing the new temp sensor I ran the engine at idle in my drive for about 20 minutes and it was 45 degrees outside.

I think you are on the right track. Clean the connections and see what happens.

Thanks for your thoughts - very much appreciated!