ColoradoReatta Posted July 8, 2022 Share Posted July 8, 2022 Does anyone know the cause/remedy of the Service A/C light? My Air Conditioning seems to work fine. Blows cold air, no problem. I'm guessing the sensor/computer is just detecting some variations in the system? Is there an easy fix just to get the light to go off? Or is this a sign of something bigger? Thanks! Link to comment Share on other sites More sharing options...
2seater Posted July 8, 2022 Share Posted July 8, 2022 Has this system been converted to R134? If the charge is a little off it seems to be more sensitive with 134 than R12 as the pressures are a bit different. Link to comment Share on other sites More sharing options...
BlakesReatta Posted July 8, 2022 Share Posted July 8, 2022 My system was converted to R134 in my 1990 and every now and then the service AC light will flash on for a few seconds and then go off. The silver 88 Reatta I had blew ice cold and sometimes I would get a message on the CRT that a climate control problem was detected. If it works, it works. The AC systems on these cars are a little tempermental in how they operate and they trip up a lot of people who don't know how they operate with getting the compressor to come on. Most people try to jump a wire from the compressor to the fuse box when the easy and proper fix is to disconnect the battery and then reconnect. The 88s have a sticker on the top of the radiator with these instructions but I believe my 90 doesn't. Link to comment Share on other sites More sharing options...
ColoradoReatta Posted July 8, 2022 Topic Author Share Posted July 8, 2022 Ok Cool! I'll ask the person I bought it from, but I doubt it's been converted. If it hasn't been converted, what does that mean? I assume, no one will service the R12 anymore? Link to comment Share on other sites More sharing options...
Ronnie Posted July 8, 2022 Share Posted July 8, 2022 You can tell if the AC has been converted to 134a by looking at the fittings. If converted to 134a there should be an adapter added that looks like the one with the blue cap in the second photo below. I think that is a photo if my '88. 1 Link to comment Share on other sites More sharing options...
Padgett Posted July 8, 2022 Share Posted July 8, 2022 Are two stages of "low AC" the first stage can occur on a cool humid day and go away. The second "very low AC" disconnects the compressor. Only gauges can tell. Being a Flordian all of my cars have AC, have the tools, and the time to do it right (pull a hard vacuum (under 100 microns) & let sit overnight to detect any leaks...) Link to comment Share on other sites More sharing options...
ColoradoReatta Posted July 8, 2022 Topic Author Share Posted July 8, 2022 Yes! Mine has been converted! To R134! Yaaaay! So, now what? hahaha! Thankfully, here in the Rocky Mountains, I don't really need AC....but...I hate that the light comes on... Link to comment Share on other sites More sharing options...
BlakesReatta Posted July 8, 2022 Share Posted July 8, 2022 Have you measured how much freon is in the system? A low reading is the most common thing to trip the light from my experience. 1 Link to comment Share on other sites More sharing options...
ColoradoReatta Posted July 8, 2022 Topic Author Share Posted July 8, 2022 (edited) Ah! Ok...Great idea! What tools do I need to measure the freon level? And...Is it fairly easy to add more? Never done any of this before. My dad used to pump freon into cars all the time in our garage....but I was pretty young then... Edited July 8, 2022 by ColoradoReatta Link to comment Share on other sites More sharing options...
Nailhed66 Posted July 8, 2022 Share Posted July 8, 2022 What I’ve found with my ‘88 (R134 converted) is that the low pressure sensor is sending a low refrigerant signal when the temperature is a bit cooler here. I just clear the codes, turn off automatic climate and roll down the windows. When the temperature is truly warm enough for AC, the system blows ice cold with no issues or warnings. In my experience,You can drive yourself crazy chasing nonexistent leaks and adjusting pressure levels only to learn that the low pressure sensor is very sensitive to temperature related R134 pressure fluctuations. 1 1 Link to comment Share on other sites More sharing options...
ColoradoReatta Posted July 8, 2022 Topic Author Share Posted July 8, 2022 2/70 Air! 2 Windows Down, 70 Miles Per Hour! 1 Link to comment Share on other sites More sharing options...
Padgett Posted July 8, 2022 Share Posted July 8, 2022 Top down is better, I just have some golf caps. 2 Link to comment Share on other sites More sharing options...
BlakesReatta Posted July 11, 2022 Share Posted July 11, 2022 (edited) You can measure the freon with gauges. I'm honestly no expert with it. My dad is a retired mechanic and he has a set of gauges. When we service the AC on my cars, he will connect the gauges and a can of freon and I'll turn the AC on and it will take in the freon. There's a certain pressure at which the freon is full in the car. You can also buy freon with a gauge on the can with the hose. They run about $30 at Walmart the last time I saw them a few months ago. My mom and I were shopping at a discount store recently and I just about fell over seeing the price of a small can of freon at $7 a can. She said she remembers it being like 75 cents a can in the mid eighties. Only two years ago it was like $5 a can. Honestly, I wouldn't worry about the AC light on if it is blowing cold for you. These cars are old and the sensors are sensitive and sometimes don't function properly. I've seen a Reatta that had a bad oil pressure sensor. When you would rev the engine, the oil pressure sensor would act like a tachometer and go up instantaneously with the RPMs. Lol it was a bit comical. My washer fluid light likes to stay on in my 90 vert. Some people talk about removing bulbs especially for the brake light. I don't really recommend doing that and I don't know how it is done either. Edited July 11, 2022 by BlakesReatta Link to comment Share on other sites More sharing options...
BlakesReatta Posted July 11, 2022 Share Posted July 11, 2022 Colorado does get hot sometimes in the summer especially at the elevation when the sun is out and the sky is clear. I know as I've spent some summers there driving my aunt's 98 Honda Accord. Cars there absorb heat just like anywhere else even though it might be pleasant outside. If you get going down a steep grade, roll your windows down and let some fresh mountain air in while you can; it'll blow the heat out. Have you driven up to Pike's Peak yet in your Reatta? Link to comment Share on other sites More sharing options...
Ronnie Posted July 11, 2022 Share Posted July 11, 2022 I have to add at least one can of freon every spring after my car has not been used much over the winter. I've had to do that since I bought it. Most of the time when I use the AC I have the windows rolled down at a stop light or something. I enjoy my car with the windows down. It makes me feel like I'm driving a sports car. 1 Link to comment Share on other sites More sharing options...
ColoradoReatta Posted July 11, 2022 Topic Author Share Posted July 11, 2022 Great insights here! Blake, I definitely am able to drive around here in the foothills with the windows down and rarely need the A/C. Especially on a day like to day when I wake up to 50F! It's like winter made a comeback! Like Ronnie said, it's more fun with the windows down anyways. I have not had a chance to drive up to Pike's Peak. That is a fabulous idea though! I've only been up there on the old cog rail train! You get pretty dizzy at the top and can't stay up there very long! Link to comment Share on other sites More sharing options...
ColoradoReatta Posted July 11, 2022 Topic Author Share Posted July 11, 2022 Ronnie, how easy is it to add a can of freon? Is there a "how-to" somewhere? I've never messed with that. Just curious...that would probably take care of the A/C Light. Link to comment Share on other sites More sharing options...
Padgett Posted July 11, 2022 Share Posted July 11, 2022 I have complete gauges for both R12 and R134a but for just touching up 134 I use one of these. I usually shot for 30-35 psi on the low side at fast idle. Can also monitor at BD27 and 28. Link to comment Share on other sites More sharing options...
ColoradoReatta Posted July 11, 2022 Topic Author Share Posted July 11, 2022 Sweet! When you get a chance, do you mind sending me a photo where the port is under the hood for that? Link to comment Share on other sites More sharing options...
Ronnie Posted July 11, 2022 Share Posted July 11, 2022 4 hours ago, ColoradoReatta said: Ronnie, how easy is it to add a can of freon? Is there a "how-to" somewhere? I've never messed with that. Just curious...that would probably take care of the A/C Light. It's pretty easy to do. Go to you local auto parts store and tell them you need a filler hose kit and a can of freon. Follow the instruction in the video below for adding the freon to your car. 1 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now