: 95 deville 4.9 cooling fan & ac fan dont work

10-22-12, 07:29 PM
hi having some issues with both my fans not working at all.have a 95 deville 4.9.i can send power through both wire harness that plug upto each fan and get the fans to run the coolling fan by itsself,and when i do the ac fan both run.tested the 1 mini fuse under hood,as well as the 50 max fuse also checked the 3 relays for power and switched them out,figured all 3 cant go out.replaced a thermostat and coolent temp sensor,any other ideas?i had it hot wired to battery 2day but really dont wanna do that.not sure if i have a loose connection to a screw or bolt that is common,kinda seemed to have an issue getting power on the ac fan earlier when piercing the wire w power probe.thanks for any help

10-22-12, 10:22 PM
any1 2nite,like to mess with it 2morro for the 3rd day in a row after work.thanks

10-23-12, 04:54 AM
Not sure on your '95, but there is usually a control module for the cooling fans, and another one for the heater blower. I needed a module for my '85 heater blower, not avaliable. So I found a GM pigtail to use a later model module for that. That pigtail was $72 bucks from GM.!....three wires and two plugs ! At least it works good....
Maybe someone here has a '95 manual for some info for you.

10-23-12, 05:18 PM
not much help autozone,advanced and caddy dealer say it doesnt have a fan switch or fan module,caddy dealer says the fans operate of the computer.thanks though anyone else

10-23-12, 05:45 PM
Is the car actually overheating?

What happens when you turn the A/C on? Do the fans turn on?

10-23-12, 08:10 PM
well my overflow has a few holes in the bottom,but since ive had the car for about 2-3 yrs ive just kept the radiator full w no problems,few weeks ago when i came home from work i heard it bubbling in the overflow which never happend before.with the a/c on the ac fan doesnt run,i have power and ground to both fans and the run with my power probe with power sent to them,the fan runs by itself when done,and when i send power to the ac fan both fan run as like a seris/parrell.like i said i can even locate each relay to both specific fans and power them on the wire right under the relay so dont seems to be fuses,relays all fuses were tested and rwlays switched.just bought a book from the store and i see that all of the wires in the diagram run to the pcm.wondering if i should pull the pcm and try and locate those fan wires.

10-25-12, 10:39 PM
i dont think its very likely that its the pcm , im checking my manuals now


what is your location and what are the temperatures outside over the past few days?