So it’s just removing a bracket correct? Not actually disconnecting a line and having fluid drain out?
Just remove the bolt holding the bracket to the fan shroud.
Just plugged the new fan in and turned the car to accessory mode and turned AC on and nothing. Brand new fan didn’t spin. I’ve determined The fuse and relays are good which i’ve determined by swapping them around with the wiper relay. Why is this damn fan not turning on!!?
I think the compressor clutch must be engaged and there must be sufficient pressure in the A/C system for the fan to be needed; the engine must be running.
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Sorry to pop in again but your troubleshooting leaves some holes. Did you ever determine that there was power at the relays? It looks like there are three fuses according to mustang man’s diagram. If after swapping relays, putting 12v on the fan would have confirmed the fan is good or bad. But yeah, engine on, ac on, but I’ll defer to others that that should turn the fan on in a cold engine. I just have never noticed that myself, but I’m in Minnesota and don’t want the fan running at all in the winter. Just for fun you can put battery power to the old fan to see if it runs to confirm it was bad.
I use a battery charger for a 12v power source when working on trailer lights etc.
I just drove the car for 20 minutes on the highway and then parked in my driveway. Turned the AC on full blast and looked under the hood and fan wasn’t moving. I also jumped the low and high fan relays with a paperclip and the fan didn’t spin.
What is going on? Is there any other possibility besides is the connector for the fan to be bad but I think thats very unlikely especially since it looks to be in good condition when visually inspecting it. Could the fan i just purchased be faulty? Doesn’t seem likely at all either
Do you mean confirm there’s power for the socket in the fuse box which the relays plug into and not the relays themselves? I’ve confirmed the relays themselves are fine because I swapped the fans with the wipers and got power to the wipers both times
If you plug the relays into a dead socket nothing will happen until that socket is energized. Just like plugging in a lamp into a dead socket in the house. Is it the lamp, the socket, one the switch not turned on? Nevada said you have to run the car with the ac on to energize the relays. Still would be nice to know if the old fan was in fact bad.
I’m outta here shortly though because I hate electrical problems, can no longer remember how to read a wiring schematic, and getting beyond my pay grade. Nevada and mustangman are good sources.
I tried running the engine right now and turning on the AC and still the brand new fan isn’t on. The fan relay fuse is good and both fan relays are good. I’m pretty stumped. Unless with this specific car the fan won’t always come on with the AC on? I just drove it for 20 minutes and been sitting here idling for another 15 minutes and the temperature gauge just started to creep up past halfway just now. So this means the fan isn’t turning on
I just started my car up in the garage at 50 degrees, turned the ac on and the fan ran. So Nevada is correct (mine is Gm though). Check all three fuses with a multi meter. Sometimes they can look good. Check any wire connection plug the plug to the fan and the wire for any opens using an ohm meter. Things get rough up there in the engine bay. If nothing else can be found you’ll need the schematic and a meter to verify wires are good.
When jumping a relay with a paperclip to test it does the car have to be completely off? Or can it be turned on to accessory mode or does it not matter
Many cars do not bring the fan on via a signal from the a/c clutch, but the pcm monitors the high side pressure in the a/c system and turns on the fan only when needed.
This car appears to have an A/C pressure sensor, the fan will be switched on at ~ 225 psi. If it is cold, the system will not reach that pressure.
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You use the paper clip to take the place of the relay. But like mopar and Nevada said, the socket won’t be energized until you reach those parameters. So maybe go for a ride and maybe all is well.
Just drove for 20 minutes and Idled for 10 minutes and after 10 minutes idling the temperature started going up so i turned the car off. I wasn’t looking under the hood to see the fan while idling but since it started overheating it’s probably safe to say the new fan didn’t kick on especially since it didn’t kick on with the AC or jumping with a paperclip… I’m pretty stumped. Relays and fuse for relays all appear to be fine and fan is brand new.
Ok I’m just about outta here but there are three wires at the plug to the fan. A hot for low speed and a hot for high speed. The third wire is to ground. That ground wire needs to connect to something metal so I would check to make sure the connection is good and you have a good ground. I can’t tell exactly what the three fuses do at this point. Maybe the sensor that reads the temp is not doing its job I dunno. Goose chase.
Remove the low speed relay and insert the paperclip, measure the voltage of the paperclip, should be 13 volts. If no voltage, there is power supply problem on that circuit.
Assuming there is ground to the relay circuits…If the fan isn’t turning on at all when i jump the relays with a paperclip does that eliminate something such as the cylinder head temp sensor being bad?
It doesn’t matter. Key on or off, the fan will run.
Did you jump the fan before you decided to replace them? Sounds like you didn’t.
I did. That was the first thing I did. Both times for jumping the low and high pins 87 and 30 with the paperclip the fan didn’t turn on. So just to confirm this with a second test i put the wiper relay (which was working) in the low and high fan relay connectors and turned on the AC and neither low or high with the wiper relay turned the fan on. Also since the fuse wasn’t blown either I figured it HAD to be the fan itself. I replaced the entire fan last night and it still won’t turn on with the AC and the car still overheats at idle only. I drove about 20 minutes to warm the car up (didn’t overheat while driving) and then I parked and waited and after about 10 minutes the car started overheating again.
I was asking if key on/off mattered when jumping the relays because I was only trying with key off so i thought for a second that maybe IF the paperclip test had to be done with key on that the test I did was getting a false positive for the relays not working. But thinking about it more, switching the wiper relay and having the wipers work with both high and low fan relays eliminates this possibility.
At this point is it accurate to say either the fan relay circuit/connectors aren’t getting power (very unlikely because the surrounding relay circuits such as the wipers are getting power), the fan connector is no good (unlikely because there’s no physical damage at all on it) or the brand new fan is bad (very unlikely)