AC question - ZR-1 Net Registry Forums

Pumpman · 07-20-2014

My AC stopped working. I disconnected the Neg. Battery cable for a couple minutes and it re-set. Working fine now. First time this has happened. Should I be looking deeper for a root cause? Is some component on the way out?

Schrade · 07-20-2014

What do you mean by 'it re-set'?

Was there an A/C Controller code that read out, and is gone now? Or did the function 'restore'?

If you did not have a Hardcode DTC, then the time factor shutdown-restart WITHOUT DISCONNECTING THE BATTERY, could have done the same thing???

Kevin · 07-20-2014

if you end up needing a new compressor i suggest discountacparts.com

KILLSHOTS · 07-20-2014

Interesting. One thing I've noticed - both with my '90 Z and my old '87 convertible - is that the A/C always comes on full-blast when I start the car the first time after a battery disconnect. Not sure if the two issues are related somehow. Good luck.

gbrtng · 07-20-2014

Quote:

Originally Posted by Pumpman

My AC stopped working. I disconnected the Neg. Battery cable for a couple minutes and it re-set. Working fine now. First time this has happened. Should I be looking deeper for a root cause? Is some component on the way out?

Probably marginally low on freon - watch for a blinking LED in the control panel which is the tip-off.

Pumpman · 07-20-2014

By Re-set I assume there was some kind of programing reset in the ECM. I do not have a code reader.

Pumpman · 07-20-2014

I believe that in 91 the AC refrigerant is still R12. Fortunately I stocked up on R12 back when it was about to be banned as my 73 uses R12 and I didnt want to make a costly conversion.

gbrtng · 07-20-2014

with an automatic AC control:

* Disconnect the small/rear connector on the liquid line to enable the fans full time. The
fans run continuously as soon as the engine starts - you need air flow thru the cooling
stack for the AC system to operate efficiently.

* if the system is really low on freon, the AC control will flash an LED, so you disconnect
the battery for a minute to clear error codes. Apparently the compressor may not run
if one or more codes are stored.

* connect a can of freon to the dryer(?) and completely open the can valve - freon will now be going into the system
at about 100 PSI - dunking the can in hot water will help speed the process. Remember to purge the
hose before connecting to the dryer.

* connect the battery and start the engine - the AC will be in the auto mode by default - set the blower speed
to 10 and the temp to 60.

* the compressor should be cycling or running full time by now. If cycling, the "on" time should increase to 100%.
If the freon level is too low, the system will set a code again and the compressor may not run at all, so you
add more freon and start over at step one.

* measure vent temperature - one can brought the temp down to 48 degrees with outside temp of 82.
This was with a system low enough to set a code and the compressor would not run.

TGF

Pumpman · 07-20-2014

Thank-you for the detail. Was very helpful.

diamond zr1 · 07-20-2014

I was always told NOT to add liquid/by turning the can upside down/ to the system/mabe a a/c expert can chip in/joe

07-20-2014	#1
Pumpman Join Date: Nov 2013 Location: Cape Coral, FL Posts: 20	AC question My AC stopped working. I disconnected the Neg. Battery cable for a couple minutes and it re-set. Working fine now. First time this has happened. Should I be looking deeper for a root cause? Is some component on the way out?

07-20-2014	#2
Schrade Join Date: Dec 2012 Location: NC Posts: 1,786	Re: AC question What do you mean by 'it re-set'? Was there an A/C Controller code that read out, and is gone now? Or did the function 'restore'? If you did not have a Hardcode DTC, then the time factor shutdown-restart WITHOUT DISCONNECTING THE BATTERY, could have done the same thing??? __________________ I'm getting my snappics / threads removed blindly as fast as I can, to get in compliance with copyright / license TOS on the boards here (lots of FSM pages and other copyright / license violations on my part; sorry guys). And thanks to all the guys who didn't whine when I posted those FSM copyrighted / licensed stuff in my threads... ( :thumbsup: [b]and to think I complied with a mod's request to delete a pic of him in a Challenge Car in NCM Museum, so he wouldn't get in hot water)[/b] Thanks to several guys here for sending parts FREE; BearlyFlying, WeGone, Geezer, GoldCylon, and more there, TonyD, mike100, fletchusmc... 1990 #2794; 4L60e Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless, Power Effects 3" [IMG]https://lh5.googleusercontent.com/-GHpfzty7DVU/UQn-0Ru2xAI/AAAAAAAAA14/08mz1p4QLD4/s445/Screenshot-5.png[/IMG] Last edited by Schrade; 07-20-2014 at 01:30 PM.

07-20-2014	#3
Kevin Join Date: Jun 2005 Location: pittsburgh Posts: 4,632	Re: AC question if you end up needing a new compressor i suggest discountacparts.com __________________ It's not the car, it's the people - Doug Johnson 90 r/r "KEYS ON" nick named "T.L.B"

07-20-2014	#4
KILLSHOTS Join Date: Feb 2014 Location: AZ Posts: 860	Re: AC question Interesting. One thing I've noticed - both with my '90 Z and my old '87 convertible - is that the A/C always comes on full-blast when I start the car the first time after a battery disconnect. Not sure if the two issues are related somehow. Good luck.

07-20-2014	#6
Pumpman Join Date: Nov 2013 Location: Cape Coral, FL Posts: 20	Re: AC question By Re-set I assume there was some kind of programing reset in the ECM. I do not have a code reader.

07-20-2014	#7
Pumpman Join Date: Nov 2013 Location: Cape Coral, FL Posts: 20	Re: AC question I believe that in 91 the AC refrigerant is still R12. Fortunately I stocked up on R12 back when it was about to be banned as my 73 uses R12 and I didnt want to make a costly conversion.

07-20-2014	#8
gbrtng Join Date: Feb 2006 Location: San Antonio area Posts: 1,179	Re: AC question with an automatic AC control: * Disconnect the small/rear connector on the liquid line to enable the fans full time. The fans run continuously as soon as the engine starts - you need air flow thru the cooling stack for the AC system to operate efficiently. * if the system is really low on freon, the AC control will flash an LED, so you disconnect the battery for a minute to clear error codes. Apparently the compressor may not run if one or more codes are stored. * connect a can of freon to the dryer(?) and completely open the can valve - freon will now be going into the system at about 100 PSI - dunking the can in hot water will help speed the process. Remember to purge the hose before connecting to the dryer. * connect the battery and start the engine - the AC will be in the auto mode by default - set the blower speed to 10 and the temp to 60. * the compressor should be cycling or running full time by now. If cycling, the "on" time should increase to 100%. If the freon level is too low, the system will set a code again and the compressor may not run at all, so you add more freon and start over at step one. * measure vent temperature - one can brought the temp down to 48 degrees with outside temp of 82. This was with a system low enough to set a code and the compressor would not run. TGF __________________ “Buy the best example of what you want, and pay whatever it takes. That way, you cry only once.” ~ Bruce Meyer

07-20-2014	#9
Pumpman Join Date: Nov 2013 Location: Cape Coral, FL Posts: 20	Re: AC question Thank-you for the detail. Was very helpful.

07-20-2014	#10
diamond zr1 Join Date: Sep 2006 Location: diamond lake /washington Posts: 223	Re: AC question I was always told NOT to add liquid/by turning the can upside down/ to the system/mabe a a/c expert can chip in/joe