• Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-

1998 V6 - AC compressor clutch wont engage

  • Thread starter Thread starter Idkwhoyouare
  • Start date Start date Jul 26, 2018
I

Idkwhoyouare

New Member
Jul 26, 2018
3
0
1
NC
Jul 26, 2018
#1
  • Jul 26, 2018
  • #1
So classic idiot mistake - trying to "Top-Off" the AC system and ended up overfilling it. Even more so ran the AC until it stopped working.

I purchased some AC gages and the static pressure was reading 120 PSI for 95 F and ~70% humidity. I evacuated some of the freon hoping this would solve the problem but the AC clutch still won't engage.

From researching online it looks like people recommend testing your AC clutch by providing 12v and seeing if it blows cold. Also by testing the high and low-pressure switches by jumping them. Another thing is to check the AC compressor relay which is located in the CCRM.

I've tested both pressure switches by sticking a copper wire in the connector coming from the wiring harness. My next plan is to test for voltage going to the AC compressor clutch and then trying to jump it. If it jumps and blows cold then the next step would be to check the CCRM?

I've also checked a fuse (I think #6 inside the car) which the owners manual said went to AC. I'm assuming there are others to check?

Anyways, any advice would help I am new to working on cars (If it wasn't obvious). I've been working on this for a few hours and realized that I made a mistake by messing with the AC without knowing what I was doing.

Thanks
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,060
21,222
234
Box behind Walmart
Jul 26, 2018
#2
  • Jul 26, 2018
  • #2
I'll have to put a tag on this thread. If I had a dollar for every time I posted about these cans...
 
Reactions: Neuron
I

Idkwhoyouare

New Member
Jul 26, 2018
3
0
1
NC
Jul 26, 2018
#3
  • Jul 26, 2018
  • #3
Noobz347 said:
I'll have to put a tag on this thread. If I had a dollar for every time I posted about these cans...
Click to expand...
Haha I'm an idiot I realize but any help would be appreciated
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,060
21,222
234
Box behind Walmart
Jul 26, 2018
#4
  • Jul 26, 2018
  • #4
Have you identified a leak anywhere? At this point, you would need to find the leak or identify that the compressor is dead.

Let's ping @jrichker . He can show you the home side even if that ends up being more technical than some are willing take on.

For me, most A/C stuff goes to an auto A/C service technician. It's generally a painful bite at once but there are tools necessary for A/C specific work that I do not possess (and I have a number of tools).
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
Jul 26, 2018
#5
  • Jul 26, 2018
  • #5
Help me to help you. TEST for key on +12 volts on both sides of the low pressure cycling switch with the AC mode control switch in the AC position. Use a KNOWN good ground.

Better yet. Use a test light that will "load" the circuit.

What to do next depends upon the detailed results.

If there is no power at the low pressure switch, THEN look for an electrical problem upstream.

If there is power at the low pressure switch THEN more tests are needed as the trouble shooting is more involved.

If you perform the tests and post the results I believe you can at least know before going to a professional what's isn't working.
 
Last edited: Jul 27, 2018
Reactions: chasM

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
Jan 16, 2020
#6
  • Jan 16, 2020
  • #6
To @chasM: If there is NO key on power at the AC low pressure cycling switch, then look for:
  • the key is not in the run position.
  • The AC mode control switch is not in the AC position
  • The AC fuse is blown.
  • There's a wiring fault up stream from the low pressure switch.
For the 1996-1998 Model year the fuse to check is the I/P #6.

For the 1999-2004 model year the fuse to check is F2.23

1999-2004 MY fuse panel schedule:

1999 Mustang GT with 2001 motor swap, wont fire. Please help

First off thank you for taking the time to read this, I hope that you will be able to help me out in some way to get a 4 month project off the ground and back onto the streets. I'm not a master mechanic but know just a little bit, enough to do your typical maintenance, overhauls, and swaps. I...
www.allfordmustangs.com
 
You must log in or register to reply here.

Similar threads

82 Gen 1 Coyote Swap AC Questions...
  • thinkfaster
  • Aug 14, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
1
Views
360
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Aug 15, 2025
thinkfaster
F
AC Compressor Power & Contour Fans
  • Fri Guy
  • Aug 27, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
10
Views
387
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jun 15, 2026
BoostedRed89gt
D
1999 G/T 4.6 A/C clutch not engaging.
  • David B.
  • Apr 26, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
2
Views
277
1996 - 2004 SN95 Mustang -General/Talk- May 8, 2025
David B.
D
J
2003, 3.8l with air conditioning problems
  • Jimb0z '03
  • Nov 3, 2024
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
6
Views
481
1996 - 2004 SN95 Mustang -General/Talk- Nov 4, 2024
Jimb0z '03
J
A
Strange AC issue
  • Adanesahde
  • May 3, 2025
  • SN95 4.6L Mustang Tech
Replies
7
Views
393
SN95 4.6L Mustang Tech May 3, 2025
Mcmahst
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?