Oddball a/c warning light on 87 Euro 3.2 Mondial

I have a garage queen 87 Italian spec Mondial 3.2 cab which was gifted to my wife from her dad. It had not run in 5+ years. After new fluids, belts, filters, tires, etc., I am amazed how well it works. Idles perfectly, runs cool in traffic, starts easily, shifts well, etc. A joyous thing to spend a Sunday roaming around Tuscany in (as my wife and I did in it yesterday). These cars are undervalued.

The car has the oddball console of warning lights between the seats. One ‘yellow’ error light is on - the one for the a/c. No doubt the a/c has no gas in it; I have not tried to run the a/c as it is 17c here in Bologna, so no need.

Strangely, neither my owner’s manual nor my Mondial service manual describe this warning light panel or what this warning light is trying to tell me. The warning lights between the seats are not covered in either manual. Maybe I am missing a supplement for the 3.2 service manual. I know the owner’s manual is the original one for this car.

Does anyone know what the amber ‘a/c warning light’ is meant to warn me about? Low refrigerant is my guess, but as I will probably use the car with the top down 95% of the time, I don’t really care that much about the a/c.

 

Not to state the obvious, but it means that there's something wrong with your air conditioning.
Alden

 

I should clarify a little bit on my statement, the warning lights on the console are not like plugging your car into a computer these days. It doesn't give you a code or tell you specifically what's wrong. It just says something is wrong. I think the reason they did away with them a year after your car was built is because they were so annoying and vague.
Alden

 

Thanks, I have never owned a car of that vintage which had a light assigned specifically for a/c issues. I thought that warning lights generally address things that might strand you. Certainly I can check the gas; the vagueness of this system is something else.

I am actually going to Modena today to get some parts for another car; I will inquire at the factory and report back.

 

John the warning light is the result of either a too low or a too high refrigerant pressure and is triggered by the high/low pressure switch, also cutting the power to the compressor to prevent damage to either the compressor (by a potential lack of oil) or the rest of the system (over pressuring).

 

The good thing about this warning light is that it tells you the cause of an AC malfunction is related, or not, to the system pressure.

 

Thanks for this - my guess is low pressure, the a/c has probably not been switched on in a decade. Next stop is to diagnose any leaks. The issue will be converting it to modern a/c refrigerant.

 

You're welcome - yes, most likely low/no pressure.

I converted mine to R134a over 10 years ago without any issues linked to the switch.

You must change the compressor oil to the correct spec, replace the receiver/dryer and all the seals that you can easily access.

Preferable, but lots of work, would be to change the hoses to ones compatible with the new gas as the old ones are usually chemically porous to the new gas, so you'll have slow leaks.

The downside of the new gas is it's lesser cooling capacity compared to R12, so the updated AC is less powerful than it was originally.

And I agree on the Mondial being undervalued. Mostly from people who don't own one, nor driven one.

 

Just fill the system with r416a and call it a day. It's basically r134 with the required (small) amount of hydrocarbon gas that will properly handle the original oil.

While you are there you can replace compressor oil with POE (NOT PAO) oil.