Hi All,

Ive owned my GX470 from the beginning, always done mainteance etc, no issues. Today it has 200K miles and AC stopped working. The panel for the AC buttons will not light up or do anything however all navigation and other systems and screens work fine, just not Climate, it throws that error. I checked all fuses and relays and everything is fine, radio also works etc. No after market products at all on this one. What am I missing here?

 

If you have illumination from the other switches on the dash, there's no reason why the heater control panel shouldn't light up.
Pins 12 & 22 go to shared interior lights
Pin 11 goes to ground behind the center of the dash

Also check fuse ECU-B, since that runs the A/C ECU (behind the right side of the dash) It is common for this fuse to go bad after 15+ years.

Chip H.

 

Hi Chip,
Yes sir, all of the other things light up and no issues with functions either, just the AC/HEAT buttons wont work, everything else works just fine, even the turn signals, Passenger airbag lights etc. When you say the ECU-B fuse, behind the right side of the dash, where do you mean inside the car or under the hood? I believe there are only 2 fuse boxes, one on the Drivers side kick panel and the other in the engine bay near the battery itself.

Thanks
Gary

 

According to Toyota, there's actually 4 fuseboxes (they count the two small ones by the under-hood fusebox separately).

The ECU fuses are in the main fusebox in the engine compartment. There are two 10-A fuses - ECU-B and ECU-B No.2

Chip H.

 

I had ordered an AC Amplifier which I replaced today,(Didnt mount it just swapped the wires over to the one i bought on ebay) AC buttons and stuff started working however now noticing the ac clutch is not engaging. Solid AC Light in the car, not flashing or anything. Double checked all the relays and fuses etc, they all seem good. What am i missing here? I dont think it could be freon because my AC has never had an issue and prior to this AC Amplifier issue, my AC was blowing Ice cold. Help..........

 

Went to a mechanic guy today that told me that my Freon is full, all relays work, and all fuses are good to go. He stated the Compressor is not getting power but wants $80/hour to chase this down. Anyone know what this might be before I open up my wallet to this guy?