working on a 94 Legacy L that came from factory w/o Cruise control an aftermarket cruise control was added by a subaru dealer back in like 97ish. the cruise control quit functioning. I was looking at similar year models and it doesn't look too hard to "transplant" the cruise control from on that has a factory install. the question is "do all the OEM ECU's contain the capability to operate the Cruise control or do I need to swap the ECU?

Factory cruise control is operated by a seperate computer.

 

to transplant you would need from donor

 

-Cruise computer and connector w/ wires

-Vacuum pump from underhood...passenger side low on the framerail

-Clutch switch if manual

-4 pole brake switch (DPST)

-"cruise" on button

-Vacuum actuated throttle cable