fault light turns on when the air conditioner is turned on

I have 2000 model 206 xr, I changed the new oil spark plug at 188 thousand km or so timing belt v belt and recirculation engine changed

Now the problem is that I turn on the air conditioner, it blows cold, there is no problem from it but this time it started to turn on the fault light

I wonder what's wrong? By the way, I got the LPI just got 3 thousand.