AC intermittent

[Aeroelastic]

Hi all, bought an imported Prado in December, the AC compressor was working fine, kicks in when the AC button is pressed.

this last 2 weeks, the AC was intermittent, sometime it kicks in sometime not. My first instinct is it’s cold so the ambient temperature is low enough hence compressor won’t kick in. But sometime when it’s 9 or 10degree like today, the AC still doesn’t kick in.

For you that has a 90 series, what external temperature will your ac compressor kicks in?

The previous owner said it was working well over the summer. When the ac kicks in, the AC freon glass in front of the radiator seems clear, not a lot of bubbles. So freon is ok?

I tried to look for the AC clutch relay but can’t find it in the engine bay fuse box. Anyone know where the relay is?

Below show the engine bay fuse box. Anyone know where the relay is? Thanks

 

[Steve Wright]

It should not matter what Temp it is it should work, but from what you have said its a lack of Gas

 

[Aeroelastic]

Thanks, any other way to confirm lack of gas apart from the little glass? There is no obvious leak and oily bit at joints. Thanks.

 

[Dave]

Check your clutch gap

 

[Aeroelastic]

Thanks, I have tested the compressor by externally applying 12v and the compressor clutch magnet operate as it should. Think compressor is ok? What you mean by the gap?

 

[Steve Wright]

Unless you have a aircon set up just take to a place to recover what gas is in there and measure it , then it can be re-gassed with the correct amount, and putting too much gas is in is not good as well,
You say there is no leak, but systems do loose gas over the years and they recomend to have it checked every two
years ( although I don't go for that)
Don't forget it is technical ileagal tovent the gas to air, so thats why its better to let the experts sort it.

 

[Aeroelastic]

Unless you have a aircon set up just take to a place to recover what gas is in there and measure it , then it can be re-gassed with the correct amount, and putting too much gas is in is not good as well,
You say there is no leak, but systems do loose gas over the years and they recomend to have it checked every two
years ( although I don't go for that)
Don't forget it is technical ileagal tovent the gas to air, so thats why its better to let the experts sort it.

Thanks, yeah aware of the legality side of thing. Was just trying to troubleshoot first to see if it is electrical related issue, like relay, which I believe can be swapped with the fog light one to test whether the relay is faulty.

will the relay still click if it is low on gas?

 

[Steve Wright]

Thanks, yeah aware of the legality side of thing. Was just trying to troubleshoot first to see if it is electrical related issue, like relay, which I believe can be swapped with the fog light one to test whether the relay is faulty.

will the relay still click if it is low on gas?

I would not think so as the presure switch won't detect and not switch on !

also the other thing, you mentioned about the gas(or not) in the sight glass, I think
you should see some in there, I had the sme on mine when the aircon stopped working
no thing showing and when it was regassed I could see bubbles in the glass

 

[Dave]

Clutch gap is the gap between the clutch plate on the front of the copressor. Youve seen it pull in, then youll see the gap before the bit that pulls in, pulls in.

 

[Deleted member 13129]

Hi all, bought an imported Prado in December, the AC compressor was working fine, kicks in when the AC button is pressed.

this last 2 weeks, the AC was intermittent, sometime it kicks in sometime not. My first instinct is it’s cold so the ambient temperature is low enough hence compressor won’t kick in. But sometime when it’s 9 or 10degree like today, the AC still doesn’t kick in.

For you that has a 90 series, what external temperature will your ac compressor kicks in?

The previous owner said it was working well over the summer. When the ac kicks in, the AC freon glass in front of the radiator seems clear, not a lot of bubbles. So freon is ok?

I tried to look for the AC clutch relay but can’t find it in the engine bay fuse box. Anyone know where the relay is?

Below show the engine bay fuse box. Anyone know where the relay is? Thanks

View attachment 164548

When the compressor kicks in you should see bubbles through the sight glass , on my Lc120 it has a label under the bonnet that says if bubbles stop when AC in on and compressor is working it needs topping up with gas/oil mix with 50 to 100 mills at the time when the bubbles first stop ,

 

[Aeroelastic]

Thanks all, seems like it’s low on gas, will get a re gas first and see what happens... lot of good learnings here.