Ls400 1995 Ac Stop Cooling After 10 Min In The Sun

[Talon]

I have the 1995 LS400 for 5 years now and I am very happy from the car. Around two years ago the engine fan broke and after it was fixed (by Lexus) my AC problems stated. The problem is that when the car stays in the sun for 10-20 minutes the air-condition stop cooling. It also happens in winter! That happens when I am driving or when it is just standing in the sun. Than I have to turn off the AC for few minutes and start it again. I may work again for few minutes and than the same again... (The AC gas is fine and the filter was replaced too.)

I was told by Lexus technician that the AC has 17 sensors (!) and one of them is faulty but to find out which one it is they have to go through all of them and that means a lot of work = a lot of money for the work.

So I am wondering if anybody had similar problem and can point me in the right direction.

Tx

[Greavett]

Hello,

Firstly we have to determine if the system is still operating when it stops cooling. So need to run the car until the A/C stops working, then we need to look under the bonnet for the A/C compressor (usually hard to see). Need to see if the end of the pulley is rotating, not the bit the belt drives but the magnetic clutch.

If we can determine that it is still running but the car is A/C is not cold it could be a Thermistor or TX valve causing the problem.

If it is not running, then we would have to find out what stops it running, I.e electrical, control, or other problems,

Hope this helps

Simon

[Talon]

Hi Simon

Thank you for answering my query. I will show my mechanic your answer and hopefully he will know what to do.

Tx

[uzz32soarer]

It's a switch on the side of the compressor. It's a tacho switch that compares tacho signal with the car. If it fails it thinks that the compressor has locked up and is turning at a different speed to engine so it turns the AC off.