Engine Engine Gets Too Warm When A/c Is On.

I am wondering if this is a problem with my radiator fan. I am wondering if it is ever kicking on. As long as I am moving down the road and air is blowing thru the radiators, I am at a good level for engine temperature. If I am in stop and go traffic and the A/C is on, it starts creaping up. I never let it get too far so I don't know where it caps out at. Once I turn the A/C off, it goes back down in temp.

Sound like a radiator fan?

Would I get any codes for this? Should I be getting a check engine light?

Thanks
 
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Check to see if the high speed fan comes on with the AC. Sometimes there's a failure and only low speed engages. At the fan connector, low is in the middle. Ground and high are on the outsides (I think high is on top but don't hold me to that).
If you see a weird little black box/bump/connector thing on the pigtail to the fan, that's a circuit breaker for the high speed. It might be opening the circuit (causing high speed to shut off after a little bit).

If you want to check in/out values for the fans, the following link might help (EDF is the low speed fan and HEDF is the high-speed fan):

https://sites.google.com/site/sn95mustangs/tech-info/94-95-ccrm
 
Ok, I ran a diagnostic on it. Using the code reader I heard the fan kick on and then it went on high for a very short period and cut out. So it appears as though the fan is working but it still doesn't sound like it is spinning at "high speed". Is that really possible? The controller must be working if it is kicking on at both levels, but it is possible that it is shutting down too quickly?

Any advice on this one?
 
Don't know what radiator you have but if it's still stock it's time to upgrade. I live in Florida and the stock radiator in the summer time was a joke. I bought a Steeda Aluminum radiator after my car was reaching 220+ in the summer. It dropped my temps to 185 all day long in the Florida heat. Sound like the fan is coming on HIGH. I ran a 180 stat, Steeda aluminum radiator 60/40 mix (60% Water) and 2 bottles of water wetter.

Here is typical July in Florida.
ClockPod2.jpg
 
You can have a situation where low and high function during the retrieval process but one or the other does not function while driving (it's a command issue). It's best to test in the real dynamic.
 
Ok so I started the car and heard the fan going. I had my friend kick on the a/c and I could hear it go faster but it was only a slight difference. When I mean slight if the hood was closed you wouldn't have heard a difference. If you were a couple feet from the car you wouldn't have noticed a difference. If you were standing next to it waiting for it you barely noticed a difference.

I know with other cars you can hear that fan kick on to get cool. I don't have enough experience with electric fans on mustangs to know the difference.

So would that be fan or controller?
 
What was going on with the power wires at the fan? If both low and high are engaged at the same time, the fan speed is only slightly higher than low alone.
 
so unplug the pigtail connector and test that way will work? It won't detect that it isn't plugged in?

What should the voltage readings be?

will a ccrm from a V6 be the same?
Answered in order:
If you do that, the car could overheat.

12.6+ Volts.

No.
 
I was only going to unplug it for the test of the voltage since I know that the high speed should be on and not the low speed when i first start the car and have AC on. It won't be running like that long.

It's on my todo list for this week.
 
Not sure where you looked this up, but Autozone.com shows two part numbers for Mustangs:

Duralast Powertrain Control Module - Base Model (V6):
part # 20261, $182.99

Duralast Powertrain Control Module - GT or GTS (also Cobra):
part #20253, $174.99