A/C Help !!

Blade2001

New Member
Apr 9, 2007
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In the middle of my drive home yesterday, A/C start to blow ambient temperature. A/C was ice-cold till then. My last charge was 3.5 years ago with R-12. I did some troubleshooting today.

Fuses looks good

Compressor clutch power didnt energize when A/C switch was pressed with car ON - amplifier didnt turn the clutch ON since one of the permissive not met ? like say high pressure switch?

I checked the pressure in compressor inlet port (low pressure port). With the car OFF, it read 110 psig!

What is this mean? my compressor is shot? if so, is there any hope of rebuilding it?

Thanks a lot for any help. Houston+broken A/C= lots of pain.

Car: 87Turbo
Miles: 187K
 

figgie

Supramania Contributor
Mar 30, 2005
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Twin Cities, Minnesot-ah
You sure the 7.5 amp fuse in the passenger foot well is not blown? I had a failure in mine where the clutch got fried and was taking the 7.5 amp out. Replaced the clutch and all was well.
 

Blade2001

New Member
Apr 9, 2007
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figgie;1114788 said:
You sure the 7.5 amp fuse in the passenger foot well is not blown? I had a failure in mine where the clutch got fried and was taking the 7.5 amp out. Replaced the clutch and all was well.

That was it!!! the fuse behind the passenger kick panel was blown.. I didn't know there was a hidden fuse that side.. I only checked the fuses in the engine bay and driver side.. Now, the A/C is ice-cold again.. thanks for all the help.. this forum makes driving supra possible..
 

Angry7M

Formerly redmaro
Sep 6, 2007
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jetjock;1114461 said:
Then your problem is not with the refrigeration system, compressor, clutch, or pressure switches. The AC signal is either not getting to the amplifier from the CC panel or it is and the amplifier is not working.


Ok so let me get this straight jetlock. If your not getting code 51 when checking for codes then problem is the amplifier?

Cause Im having the same problem with my A/C everytime I push the A/C button the Compressor Clutch will not engage and ive checked all the fuses and they are all good. It was working fine but after fixing some wiring It stopped working (the wires that were fixed had nothing to do with the A/C). I also remembering touching the Alternator with a the coil packs and it made a spark, maybe this blew something? Im lost.............and its hot oustide!

And also my the two compressor fans arent working, and what where exactly is the amplifier for A/C?
 
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jetjock

creepy-ass cracka
Jul 11, 2005
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Redacted per Title 18 USC Section 798
You should get 51 with the AC on in diag mode. As I said if not then a) The signal isn't leaving the heater control panel or b) it is but not getting past the amplifier. It has to exit the amp to turn on the clutch and tell the engine ECU AC is on. That's why the code is helpful: it splits the system into parts.

In the example above the 7.5 amp fuse was blown. Since that fuse supplies power to the heater control panel his problem was the first case. As for your second question the amplifier location is up behind the glove box and to the left...
 

suprafanatic

New Member
May 25, 2007
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well my ac didn't work and i really didn't want to mess with it.. i always go with windows down or top off anyway. just a personal choice i guess. i dont regret it...yet..lol
 

Angry7M

Formerly redmaro
Sep 6, 2007
733
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suprafanatic;1117543 said:
well my ac didn't work and i really didn't want to mess with it.. i always go with windows down or top off anyway. just a personal choice i guess. i dont regret it...yet..lol


I live in Arizona......lol and it gets a lil hot here.
 

Blade2001

New Member
Apr 9, 2007
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Well, I guess I closed this issue too early. I replaced the A/C fuse in the kick pannel, but after 1/2 hr with A/C ON, the CB next to it tripped. I reset it, to get the A/C back ON, but it tripped again. I must have a drain somewhere in the A/C circuit.. Could it be the A/C clutch as Figgie described? how do I even check that?
thanks.
 

figgie

Supramania Contributor
Mar 30, 2005
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Twin Cities, Minnesot-ah
Blade2001;1136251 said:
Could it be the A/C clutch as Figgie described? how do I even check that?
thanks.

Technically you can't

If it is taking the CB out than you are not left with too much to trouble shoot.

anyway

to troubleshoot clutch

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=AC&P=22

if it is out of spec. Well then replace the clutch. BTW Go to napa for that one. They sell what is called a Unidamper and it works quite well (been using one since mine died in 1996).
 

Blade2001

New Member
Apr 9, 2007
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Update..

A/C clutch resistance was 1.2 ohms. This was below the TSRM specs. So, I got brand new A/C clutch kit from Toyota and replaced. A/C worked fine for 30 mins. Again, it burned the 10A fuse behind the kick pannel. What else could be going on? something else is shorted out.. any tips?
 

Blade2001

New Member
Apr 9, 2007
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figgie;1157367 said:
by chance did you do a check on the clutch prior to installation? I went through three clutches prior to finding one with in spec.

Well, I found the problem.. The new clutch coil.. When I installed it, it had little bit of play in it. The snap ring was in holding it in place.. but it still moved little bit. Due to that, the pully chewed it up when the car was running. There is a small difference in thickness of the back plate of the coil that hold it in place between the original one and the new one I got from Toyota.. NOt sure if thats what did it.. couldnt find the NAPA part.. Autozone sells aftermarket clutch kit.. I could try that next..