j48i

Hi everyone,

I recently purchased a 2006 GS3 with 183k miles. I got it for very cheap because it had the notorious downshift issue. I immediately removed the ECU and sent it to SIA. The car now shifts fine, however now I’m having issues with the A/C not working. It was working fine before the ECU was sent out. Here’s a list of the things I’m noticing:

1. The A/C works fine when I first start the car in the morning or if the car has been sitting for a few hours. The air blows cold, both radiator fans are spinning, and the compressor clutch is spinning. However if I turn the A/C off and then back on while the car is still running, it no longer works. If I turn off the car off complexly and then back on, it still no longer works. I’m receiving the “Check Air Conditioner” on the screen with green A/C light blinking.

2. When the light A/C green light is flashing the compressor clutch is not spinning and the radiator fans are also not turning on.

3. If the A/C is off completely and the car is up to regular operating temperature, neither fans are turning on. I would assume one would be on even with the A/C off?

So far here’s the things I’ve checked:

- ODII scan, no codes coming back
- I’ve checked every fuse in all 5 fuse boxes
- Musical chairs with the relays marked A/C comp & Fan.
- Pulled the entire center screen unit and removed the iSimple iPhone gateway and adapter (I read on clublexus that these have caused intermittent problems with the A/C)
- Pulled the negative battery terminal connection a few times.

Any ideas what it may be? Since I pulled the ECU for repair, do I need to take the car to a Lexus dealer to have the it formatted or something of that nature? Is there a relay for the compressor clutch somewhere that I should be checking?