Vehicle 2001 Durango SLT 4x4 4.7L AWD
Ok guys here it is let's see if we can figure this out, I have my doubts I will explaine that doubt shortly.
Symptoms: overheating with AC on or with out faster with AC on of course. I have a fairly new radiator and fan clutch t-stat and H20 pump are flowing verified visually and by just driving as the temp stays with in normal range on highway with air flow. If I idle it'll get warm (second hash mark on guage ) I cool at this point by driving alum.heads cast block different contraction/expansion rates.

Alright when I was running AC the other day it was starting to warm up, I noticed then the AC
Blew warm for about 1a min then back to cold, I smelled electrical.
Replaced the Efan as the old one after plugged in 12 volts to verify it was bad and indeed it was. Replaced and checked relay all good. AC still blows cold Efan will not kick on at all. I replaced Temp sensor to no avail.
It will allow the ac to kick on and run even tho efan will not ever kick on and allow the temp to just increes. Im at a point where its dealer time (don't want to due to cost) if anyone has had this kinda thing happen let me know.
AC shouldn't as a safety protocol kickon with out signal/operation from efan.

 

bad efan relay maybe?

 

He said he replaced it but it is possible that a new one is bad. Maybe the temp the controller of the E-fan is bad. I don't know what controls it. But still the mechanical fan should be keeping up. There is a link in the DIY thread to a video on how to check the fan clutch.

 

whoops, missed that. I guess that's my dyslexic moment of the day

 

Relays are good, did some flip flopping just to check and be sure, another kick this afternoon was the blower motor resistor seemed to crap out was fine no speed/setting degradation just dropped out ug.

The belt drive/mechanical fan keep as up for the most part, with the exception of being at idle with the AC on or extended idle periods w/o AC I drive just a lil even low speeds so I am thinking its doing as designed.

I'm still all ears and entertaining all suggestions. The elec. Fan in temp controlled by the temp sensor located in front of the intake Mani dead center, which I have replaced that talks to the relay, which in turn drops voltage,ohms restriction to relay and allows fan to kick.

 

it won't hurt to check connections and contacts and see if anything's dirty or corroded.

 

Check the wiring to the fan and the harnesses for corrosion. Also test to see if the fan actually does work even tho you replaced it.

When the A/C is enabled the E fan kicks on, also when you are over temp which I think is 210 F it kicks on to help aid in cooling of the motor. So, if you start the engine and turn on the A/C then the fan should start, if not then trace for power at the fan, if still no power check the fan relay and the wiring.

Also, try to use more complete English sentences if you can, it is very hard to follow you in your statements.

 

Got it, disconnected the electrical fan connection then I started the vehicle to allow it to warm up to the designated temperature that the electric fan was designed to turn on from the coolant temperature sensor. 202-205 as per service manual.
I have read that it will only come on at a certain temperature regardless of AC being on or off, and have read that it comes on with AC activation regardless.

I did not turn on AC just brought up to temperature (almost over heating) checked the voltage with the volt meter I read 14.1 volts, OK so I have signal plugged the electric fan connector back in, it turns on!
The connection wasn't corroded nor damaged can't say why it didn't want to send voltage, but it works now and I am running cool again.

As for the blower motor resistor I removed it and disconnected it to find the number 2 input ( they are numbered 1-5) burned and had burned a bit of the insulation up the terminal wire.
This explains the electrical burn I smelled. No dealer repair, no huge bill.

Hydra I have read through many of your posts/replys in English ehh...I was using my phone in my original post so its jumpy I agree