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Discussion Starter · #1 ·
I'll try again in another thread with my problem to get a/c in my car with a coyote engine swap in a sn95 . I probably is a simple wiring circuit to get the compressor clutch to energize but from where will the circuit originate?
I have another thread in this forum but no answers so far . Probably is not possible , the engineers and tech service at Ford Racing have no solutions.
Must be someone here that knows their stuff that will have some suggestions:joy:
 

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is the sn95 dash harness still in the car and the coyote swap is just using a standalone harness?

so much info on what you did to swap the engine in the car is missing I have no clue...

BUT, if the original sn95 dash harness is still in the car. just look up the chassis wiring diagram for it and find out which wire from the a/c control panel feeds to the compressor originally and use that wire to engage the clutch.
 

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Discussion Starter · #3 ·
All of the OEM wiring is there and functional . The only thing missing is the 4.6 engine and the 4.6 engine wiring harness and the engine compartment wiring harness to the engine . The engine comp harness serves no purpose so it's gone and that is where the wire is to energize the compressor clutch.

The original CCRM and the PCM are still operational to function all the systems in the car . The coyote engine and the control pack comes with a PCM to function the crate engine, in other words it is a stand alone system, so i have 2 systems

The oem heater and A/C are all in place . I would like to think that when the A/C switch is turned on in the panel, it must connect to a relay that will close the circuit to the compressor clutch, i can jump the clutch and it works, so how to get that circuit to the relay is the question, if this is the way to get it functional . Then all i have to do is find the relay, but i have no clue where it is
 

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Discussion Starter · #6 ·
try this 94-98 Mustang Wiring Diagram and Wire Diagram

do you already have your a/c hoses? if so, where did you get them?
All the OEM lines are still in place , when I took out the 4.6 , I removed the bolts on the compressor and simply tied it to the side of the engine compartment, i didn't disconnect any lines or hoses . When the coyote engine was installed, i bolted the compressor on the engine . Now i need a belt and a wire to the compressor clutch to have functional A/C
 

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I always thought the control packs had something for A/C control. I looked at the instructions for the coyote and nothing is mentioned. I did look back at the 3V mod motor control pack and it does have a wire in the PDB for A/C control. Blunt lead #7 (violet) connects to a dash controlled a/c switch.

Any extra blunt leads that you recall that did not go anywhere? Double check your PDB again. Is there a spot in the upper left hand corner marked "A/C"? It looks like it on the instructions.
 

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Discussion Starter · #8 · (Edited)
The coyote control pack does't have a blunt lead for the A/C , the PDB does have provision for the A/C , a diode light that did glow when ign is on , the white letters clearly printed on the PDB where the diode light shines says A/C and i believe there is a relay inside to control the circuit . But Ford Racing engineers say that is only a future provision for full A/C function . There is no blunt lead ( circuit ) that i'm aware of.

I'm sure with a little effort , that a quick and dirty method of getting the a/c to work is possible but it won't be controlled by the coyote control pack and that is not good . The correct method of functional a/c is to shut off the a/c clutch when you go WOT. Only the coyote PCM can do that and the interface is not developed as yet according to Ford Racing. I can only believe what they tell me, i'm not the only one that wants a/c, the techs have lots of inquiries of this issue

I did find out the other day searching around that Roush's supercharged coyote crate has a module developed by Roush that allows the a/c to be fully functional, i called them to see if the module was for sale and they said that it was if i bought the crate engine , it's only $18,975
 

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How are you controlling the fan?

with that info it would be easy to create a seperate circuit for the a/c using the stock pressure switches, as well as retain WOT cutout via a relay.

I work with with controls all the time, and could guide you through it.
 

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Discussion Starter · #11 ·
The fan is controlled by the coyote PCM . Internal cyl temp sensor info is sent to the PCM , when 195 F is reached the fan circuit is energized by the PDB via a relay and shuts off at 190 F.
 

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Is this a two speed fan?

Are both speeds controlled by the coyote pcm?

I think that may be the case.

If so, are you looking for a temp fix, untill frpp enables the a/c function in the conversion kit?

Are you good with wiring, relays, diodes etc?
 

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Discussion Starter · #13 ·
It is a 2 speed fan . The fan control circuit from the PDB is a single wire, so I have the circuit going to the HI speed in the fan. The Lo speed is redundant and not supported .

A temp fix is fine . If you can outline the fix, i'll try to follow instructions

thanks for your help
 

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can you make coolant temp the low speed?

we need the low controlled by PDB and HI by the circuit we create, is that possible with how you have it?
 

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Discussion Starter · #15 · (Edited)
Yes, i can make Lo the coolant temp . But , when I first installed the engine I had the Lo for the coolant temp. When I was in heavy traffic with lots of stop lights on a hot day it would overheat. So, I switched to the Hi speed fan. Even at Hi it seems marginal keeping 195 to 200 F . I don't think that I would like to have a perm Lo for coolant temp control
 

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if hi is marginal in traffic now, we will have an issue, when the a/c is on, don't you think?

in normal situation, low is for coolant, hi is for a/c, therefore when a/c is used, ie warm weather, it can reject both condenser, and radiator loads.

We need one speed dedicated to the seperate circuit, sounds like low is not of any use?

are you able to remedy the cooling issue first?

you should be able to run 120 deg f traffic all day long before adding another load.
 

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Discussion Starter · #17 · (Edited)
if hi is marginal in traffic now, we will have an issue, when the a/c is on, don't you think?
My temp gauge in heavy traffic show slightly under 200 F , is that too high ?

in normal situation, low is for coolant, hi is for a/c, therefore when a/c is used, ie warm weather, it can reject both condenser, and radiator loads
I don't understand the last part ..... OK , now i get it

We need one speed dedicated to the seperate circuit, sounds like low is not of any use?
................ will do as you suggest


are you able to remedy the cooling issue first?
The 4.6 was just fine , no issues , rad was cleaned and is in good condition , Seems like the 5.0 is fussy with temps . I suppose a high performance rad would raise the bar, but not in my budget at the moment

you should be able to run 120 deg f traffic all day long before adding another load. Today 12:43 PM
Running on high it would probably do just that. Perhaps the solution would be to turn on the A/C in heavy traffic . One would likely want to do just that on a hot day :)
 

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Discussion Starter · #18 ·
Last week FFRP reflashed my PCM, I reinstalled the unit for a road test , got caught in heavy traffic and noticed my temps way over 230 F. Pulled over , Fan not working at all .

Cooled down for a bit ,drove home , temps normal ..... Checked fuse in PDB, there is a 40 amp MAX fuse for main power to PDB and it was blown , replaced fuse and ran engine until 195 F when fan kicks in , still no fan . Replaced relay and it worked fine and still ok . Cause of these failures unknown.

The OEM 97 Mustang has a 60 amp fuse in the panel and i think that is for the fan . Maybe the 40 is not enough for the OEM fan to run on HI continuous . Another source says that the fan draws 37.5 amps

Wanted to make disclosure with the recent fan problem .....:(
 

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can you email me your wiring diagrams for the control pack, I looked at the pdf from frpp, and there is provisions for a/c and fan control, that will need to spliced to the ccrm

it says functionality is out in newest revision.
 

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Discussion Starter · #20 ·
That pdf is all i have for wiring. That is what comes in the control pack ,no other wiring schematics etc is offered from ffrp AKA WYSIWYG
 
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