Cooling system issue! Replaced overflow tank, ect sensor (total nightmare!!!), thermostat, every hose, flushed system, etc. All tests good, but still fans won't come on and no coolant in top hose. Aga

find the bleeder valve to vent off the air and pour coolant in while running a cold engine. bleed air till coolant spurts out. this is how my valve looks like.

2004 cadillac deville there isnt a bleeder valve. Its a closed system. There's a bleeder line to the overflow tank. When filling Loosen top hose and pour antifreeze as much as possible in that hose then reconnect. Take the bleeder hose on top of the overflow tank stick a small funnel in it and pour antifreeze in that line . U will see the the overflow tank starting to rise a little as you do this. reconnect and run. The rest will bleed out on its own. Check fan Fusses, Ground etc. With the key off Off try spinning the fan by hand. Sometimes the fan will seize and you will not be able to spin. Disconnect the fan circuit and add a load and see if the fan operates. This will test if the fan motor works at all.