AC Compressor Woes...

[SableSal]

So I haven't had the AC operable for the past winter. Figured I would fix it around spring time. I go out and check her out, and the clutch doesn't engage. Also the system is empty. I check for leaks and don't find any.

Well, I checked out the voltage at the clutch cycling switch and jumped it... and nothing. The compressor MUST turn on at this point. But nope, nothing... I then check all the fuses and they are all good.

Now my question is... Where should I start looking to get some voltage going through the circut. Also... Any ideas on the AC issue? When the clutch was engaging, it would get cold... but not 100% cold. It's odd...

Any help is good help,


Thanks,




Sal

 

[wuzzzer]

I'd help you, but this is SHO Forum!

 

[SableSal]

Ah bah-humbug!! Yeah yeah yeah, same difference...

Sal

 

[Mr Anonymous]

Jumping the cycling switch isn't a guarantee of anything except closing that circuit. Sounds like your clutch coil isn't energizing, or the clutch hub has worn to the point that the coil can't pull it in.

The circuits on the V8 SHO and non-SHO are different. Perhaps someone over at http://www.taurusclub.com can shed a little more light on the subject for you.

 

[SableSal]

Jumping the cycling switch isn't a guarantee of anything except closing that circuit. Sounds like your clutch coil isn't energizing, or the clutch hub has worn to the point that the coil can't pull it in.

The circuits on the V8 SHO and non-SHO are different. Perhaps someone over at http://www.taurusclub.com can shed a little more light on the subject for you.

Yeah, I'd like to visit and ask... but you know how that goes.:cry:

 

[naval-avi8or]

Well, I checked out the voltage at the clutch cycling switch and jumped it... and nothing. The compressor MUST turn on at this point. But nope, nothing... I then check all the fuses and they are all good.

Now my question is... Where should I start looking to get some voltage going through the circut. Also... Any ideas on the AC issue? When the clutch was engaging, it would get cold... but not 100% cold. It's odd...
Sal

Sal,

You mentioned that you jumpered the cycling switch and the AC clutch didn't engage, did you check for 12 VDC athe the cycling switch if so did you check for 12 VDC at the electrical connector on the clutch. If you have 12 VDC power at the clutch than the clutch/clutch air gap needs replaced/adjusted.


If you have 12 vdc at the cycling switch and jumper it and don't have 12 vdc at the cltch connector than the high press switch or CCRM is bad or you have a open wire betweenn the cycling switch and clutch before or after the hi press switch.
If you don't have 12 vdc power at the cycling switch than you need to check the relay feed to the cycling switch.

 

[naval-avi8or]

Did some more reading and here's the EVMT electrical flow. Control head (EATC/Manual Control), when ac selected, out put P (Purple) wire to cycling switch. Cycling switch R/Y (Red/Yellow) wire to Dual contact High Pressure swith. Hi Press switch output DG/W (Dark Green/White) splices to PCM (pin 41) and CCRM (pin 21). CCRM directly feeds the ac cluth vie CCRM pins 23 (+/positive) and 16 (-/ground).

Once you've narrowed it down further let me know and I can tell you the individual connectors to check for and their location.

 

[SableSal]

Did some more reading and here's the EVMT electrical flow. Control head (EATC/Manual Control), when ac selected, out put P (Purple) wire to cycling switch. Cycling switch R/Y (Red/Yellow) wire to Dual contact High Pressure swith. Hi Press switch output DG/W (Dark Green/White) splices to PCM (pin 41) and CCRM (pin 21). CCRM directly feeds the ac cluth vie CCRM pins 23 (+/positive) and 16 (-/ground).

Once you've narrowed it down further let me know and I can tell you the individual connectors to check for and their location.

Cool, thanks for the help!

Hey you're in Lemoore?? Stationed there I would assume?



Sal

 

[naval-avi8or]

Cool, thanks for the help!

Hey you're in Lemoore?? Stationed there I would assume?



Sal

Not yet that's my next duty station. Departing Meridian MS on 19 June and taking a couple of weeks leave enroute to arrive in Lemoore around mid July.

I'll be glad to get close to other SHO/Taurus (Sable as well) owner and forum members. It's sucks living in podunk Mississippi. I was in Jacksonville Fl prior to returning to Meridian and it was about the same. I miss SOCAL.

Once I get there and get situated will have to try and get together.

 

[SableSal]

Not yet that's my next duty station. Departing Meridian MS on 19 June and taking a couple of weeks leave enroute to arrive in Lemoore around mid July.

I'll be glad to get close to other SHO/Taurus (Sable as well) owner and forum members. It's sucks living in podunk Mississippi. I was in Jacksonville Fl prior to returning to Meridian and it was about the same. I miss SOCAL.

Once I get there and get situated will have to try and get together.

Sounds good, most definetly

 

[Mr. SHO]

You could try the broomstick test. If that works, you can try removing the shims and possibly resolve the issue that way.
http://v8sho.com/SHO/AirConditioningCutsOut.htm

 

[SableSal]

Well, I checked voltage at the Low Pressure Switch, and found nothing... Periodically I would get about 4-5v (although I think the DMM is playing games with me). Is this normal?



Sal

 

[SableSal]

Ok, so I found voltage. The high pressure switch was unplugged. Plus I realized why too (DOH!)

Anyhow, the clutch engages and disengages well. I have two cans of freon in there right now.

Only issue is, the fan doesn't turn on when the MAX A/C is on. Is this normal? I always thought the fan would turn on to cool the condensor off.

Anyhow, any help is good help.


Thanks,





Sal

 

[Mr. SHO]

If the MAX A/C is on, at least one fan (perhaps both?) should be on 100% of the time, as far as I can recall.

 

[SableSal]

Odd thing, cause they aren't.

Anyone else care to chime in?




Sal

 

[ArkanSHO]

12 volts is not coming out of the dash or from the ECM then. I just had to trace mine down. There are two signals that need to be present to the CCRM to activate the AC: 1 is from the footbal that tells it the AC is selected and the other comes from the ECM or engine control module that tells the CCRM that you are not WOT. In my case that was the signal that was missing and my compressor nor the fans would come on. The WOT wire is a pink and yellow that can be found on the large square harness plug above the transmssion and the other wire is pink and runs to the cyling switch then through the low-pressure switch that is behind the compressor on the rigid line. I ended up supplying a 12 volt signal to replace the missing signal for the WOT signal.

 

[SableSal]

Thanks, I actually have the Compressor working again.

Added some freon, seems like there may be some air in the lines though... Don't know how. I'm going to do a evac and recharge on her this next week.

When I hit A/C, the fans don't come on right away. Is that normal?





Sal

 

[projectSHO89]

The dual speed fans are wired in parallel. They should both work simultaneously at whichever speed is commanded by the PCM.

HIGH and LOW speed is commanded under the control of the PCM. Control is switched by the H & L speed relays located in the under-hood fuse/relay panel.

It would be expected that the PCM would slightly delay fan engagement after A/C is turned on. Don't want multiple loads placed on the system simultaneously.

Steve

 

[SableSal]

The dual speed fans are wired in parallel. They should both work simultaneously at whichever speed is commanded by the PCM.

HIGH and LOW speed is commanded under the control of the PCM. Control is switched by the H & L speed relays located in the under-hood fuse/relay panel.

It would be expected that the PCM would slightly delay fan engagement after A/C is turned on. Don't want multiple loads placed on the system simultaneously.

Steve

Thank you for the info. The AC is working... But it's taking a little for the freon to cool. Also today I heard a clunk sound coming from the compressor when the clutch engaged after the vehicle sat for about 4 hours. Any Ideas?

 

[SHOZ123]

The low speed fan should come on immediately when starting the car with the EATC in a AC compressor mode.

High speed is regulated by the PCM. +210F coolant temps or more frequently the AC high pressure switch.