Thanks Emery,

I'm reasonably certain this is a non ASR car, but it definitely has a limp mode!

Would the code chart I have be wrong?

Is the Socket 7, Code 3 error actually indicating an ETA error, and not a failure of a separate Cruise control/idle speed control actuator?

I sliced the ETA harness open and inspected it, the wires are flexible and look pristine. This car came from the Japanese market so it's possible it's not subject to the normal rotting harness issue.