Hi,
 
The AC in my MR2 was not working when I purchased it. I was originally told it simply needs regassing. So I'm about to book it in for a regas and leak testing. But I notice today on a quick test drive that the green AC light does not light up when I push it. If i select Econ the green light displays but not on AC. 
 
* Fuse is fine.
* Have not removed the relay as yet, need to work out how to test it correctly.
* Fan works great on all fan speeds
* My car is JDM so has the climate control thingy.
 
Any suggestions?:
 
Could this be:
 
- Not engaging on protection as it is low on gas?
- Faulty relay?
- Faulty switch?
- Faulty wiring? (I think the wiring runs through the console is that right?...)
 
Appreciate the help. 7,000km road trip begins in 23 days. so really want to have EVERYTHING tip top by then. 
 
Cheers.

Aircon will not not engage if low gas.

The light not illuminating could be as simple as a bulb - I am unsure of the switch system so best to get other advice.

Wanted to offer advice of if you want good aircon, after twenty years of the system running, maybe time for a clean and system refurbishment;
Get the system professionally degassed
Remove the ac evaporator (undo the two pipes in the front trunk infront of passengers side foot well area / next to battery, then the four screws under the dash) then wash with dishwashing liquid and warm water. Washing is just putting water over, it's delicate like a radiator/intercooler.
Replace the Tx valve whilst the evaporator is out (estimated part cost under $100)
Replace all connection pipe Orings (cheap as but time consuming)
When getting it regased, get the a/c shop to change the dehumidifier canister (estimated part cost $30)
The above costs a bit more but can make a big difference on the a/c performance, longevity, and smell :)

Good tip Tony, Might ring to request they do a full clean up of the system (I won't have time as I'm back on shift on Wednesday).

But with a bit of luck once it is regassed perhaps the AC will work once it has correct Gas levels. 

Cheers.