At start up, AC light flashes first, then AC + Recirc lights flash 20 times. My AC is blowing warm air. Will an error message show if I'm low on 134?

Thanks

No flashing lights if you are low on R134a. The codes only show problems with the mechanical aspects of the ECC - damper motors, temp sensors, blower, AC relay, etc.

You cannot get the codes on a generic code reader. It is possible to build your own just for the ECC. Use the following diagram, but use #6 instead of #3:



After the wires are hooked up, turn the key to position II. Touch the #5 with the #16 for 1 second or less, which will light up the LED. Wait for the response, which will be a series of 3 light flashes. Count them, a 1-1-1 will mean no codes. Then go to the error code table for 1994-1995 850's: http://volvospeed.com/vs_forum/topic/47502-dtc-information/

To clear the codes, make sure you have read all of the codes, touch the wires for 6-7 seconds, wait for light to glow, touch again for 6-7 seconds.

Thanks Klaus. I'll get over to Radio Shack and get this problem solved. I'll post back to let everyone know what I find.

Built the AC code reader, only got 1-1-1. AC was blowing arm, I bought a charge kit with gauge. Charged yesterday and have 46 degree air coming out of the vents, with an outside air temp about 90.

Charged and no more codes (?)

You can get a code for a slow responding damper, usually the recirc. I run the recirc once in a while to get it used to moving. Once the damper is 'fast' enough for the ECC, the code goes away. Keep your code reader, it can be a life saver.

After putting about 1/2 can into mine a month ago, it is still working. Of course, the temps are now in the 70s. AC in my car is a bonus, it took me several months to get all 4 of the dampers working. Last resort was to remove the dash to unstick the vents.