GM techs. need help

[G..]

97 malibu 3.1
cooling fans will command on with scanner both low speed and high speed but will not come on own. A/c is not charged so not sure if A/C will command but can do so with solus.
Anyone every have this problem. Everything points to BCM or PCM but dont want to guess at it.

[greenbullitt]

didnt the malibus have a fan switch in the radiator tank? If thats the one im thinking of, they used to be quite common

[G..]

This one doesnt show to. the lumina's did though. Well they call it a coolant sensor. No wires going to radiator.

[greenbullitt]

This one doesnt show to. the lumina's did though. Well they call it a coolant sensor. No wires going to radiator.

so the ect maybe?

[G..]

so the ect maybe?

checked good but replaced anyways already. Computer shows little cooler that temp gauge reading but still gets close to 230 by scanner and temp gun and shows over 3/4 on gauge.

[Sleeper]

This might sound stupid, But i had a problem with a grandprix doing something similar. Found it when charging the a/c up.

The connector for the fans was connected nice and tight, but as well all know it was not making a good connection. Cleaned them up and he was good to go.


If not i say pcm. Does the scanner show they should be on? Or do they say off until you turn them on?

[G..]

I can command them on and they show on. Just wont get a signal to turn them on. The temp sender is sending a good reading to pcm of 227 was highest I saw. But gauge was higher it appeared. Im gonna charge ac and see if it commands a/c fans on.

This might sound stupid, But i had a problem with a grandprix doing something similar. Found it when charging the a/c up.

The connector for the fans was connected nice and tight, but as well all know it was not making a good connection. Cleaned them up and he was good to go.


If not i say pcm. Does the scanner show they should be on? Or do they say off until you turn them on?

[shumpertdavid]

cooling fans should be commanded on at 225-227 on those cars, you might let it run to 230 and see if they come on. I wouldn't go any higher than that. I never understood why gm runs them so hot.

[greenbullitt]

cooling fans should be commanded on at 225-227 on those cars, you might let it run to 230 and see if they come on. I wouldn't go any higher than that. I never understood why gm runs them so hot.

damned emmissions

[turbos66coupe]

It has got to be ect signal or its not hot enough yet. If you can turn the fan on that tells you fan,wiring, relay and fuses are good. The pcm , ect, ect wiring is all that is left

[JimD]

It has got to be ect signal or its not hot enough yet. If you can turn the fan on that tells you fan,wiring, relay and fuses are good. The pcm , ect, ect wiring is all that is left

Yep

[G..]

It has got to be ect signal or its not hot enough yet. If you can turn the fan on that tells you fan,wiring, relay and fuses are good. The pcm , ect, ect wiring is all that is left

I had already changed the ect just as a precaution. I fixed the a/c today and the fans both run on low speed while a/c is on and car never gets hot. turned a/c off but could not get temp over 220. Maybe this thing is just not getting hot enough with the mild outside temps??????????????