Hi all, does anyone know if the AC control unit from 1993 940 and 1994 940 interchangeable? The AC of 1994 944 worked intermittently, and I found one from a 1993 944 in perfect condition. Examining by eye, there are several parts on the printed board with different part numbers, but otherwise they look exactly the same. Does anyone know if I can use the one from 93 in my 94?
btw: I know the malfunctioning board can be 'reflowed', but I am one of those people who does not know by which end to hold an iron :(
If anyone know where I can find a circuit shop to have the printed board resoldered around Worcester, Mass. or Waltham, Mass, please let me know. Thanks in advance for your help.

Hi everyone, today I swapped the junk yard unit from a 93 944. After installation, I started engine, turned on AC, and popped the hood -- the compressor was not running. I unplugged the switch on the receiver and tried to short the two leads, nothing happened. Another bad unit, I told myself. Then I drove the car with it, doing laundry, grocery shopping... all in a sudden I realized the vent blew cold. My first thought was the vibration somehow made a connection, then I found the A/C OFF button was not pressed. I parked the car, popped the hood, and did several tests. It seems on the 93, the AC was on when the button was pressed? On my 94, where the button has a snow flake on it, the AC was on when it was pressed. This was really something I had not expected. Can anyone confirm this? The AC seemed to be working consistently for the rest of the day, but in the opposite way I was used to :)
Thanks for everyone's help, especially spook. Although the resoldering does not seem necessary now, I still really, really appreciate your offer to help.

I just installed a 1991 740 unit in a 94 940, now the a/c is running again as it should.... Had the same prob in my 91 745t, same fix. Only prob w/the 745t is it blows hot on accelaration........ Tom Wasney 27940aholic

Dear Masupra,

Good a.m. and may this find you well. If - after a search - you can't find someone to re-flow the solder, I can do this. I'm in the Lexington, MA area once a week. It takes only a few minutes to do this, presuming the unit is out of the car. e-mail me via the Board.

Yours faithfully,

spook

One of the old TV repair shops may do your board, or locate a ham radio club and ask them: they are usually handy with an iron.
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See the 700/900 FAQ under 'Select Link' button on the top right.

Yes. Volvo shows the same part number for both years. Part number 6848302 for the original part, and 3522217 for the upgraded part.
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john