There are quite a number of codes that will trigger the CEL ; the flashing cruise control usually comes on with the CEL.
You will need a scanner to see the code, and they charge a lot just to plug it in, unless you have a friend with one.
I got around this by buying one on line; I plugged it to the connector under the dash, and wrapped the other end around the steering column; the scanner is in the glove compt.
I can now do my own testing without even getting out of the car. The scanner tells you the code and what it is; you can then decide to delete the code...

Good luck.

 

Well, you don't list your location so that doesn't help much.

But if you happen to be in the US anywhere other than California any Autozone type store will read the codes for free.

 

CEL and cruise flashing is often a sign your gas cap is not tight or has a broken seal. Check them 1st. Takes a while to reset.

 

The scanner tells you the code and what it is; you can then decide to delete the code.

 

Once you know what the code is, there's no point in leaving it there. By deleting it, you get your cruise control back, and if a new code is triggered, you'll see it immediately. Would be nice to have your own reader.
Dealers and garages have only one purpose in life: sell parts and labor. Case in point: I read on this and other forums about someone getting a CEL & cruise; they go somewhere to have it read; turns out it's P2238 . So they replace the throttle position sensor (TPS), at the pedal location. He goes away happy after paying the bill...
4 months, the CEL & cruise come back on!! Off to the garage, and the same thing all over again; no warranties though, it lasted past the warranty period. Another payment. Would be nice to have your own reader.

That happened to me, but I wised up soon enough. Got the CEL & cruise, and the engine went in "limp" mode: idle only, and 10mph to the next exit, then halfway up the ramp, the car stopped: not enough power.
Called the tow truck, took the car to my favorite garage, but it was closed. Paid for the tow, and 2 hours later, I'm back home. The next morning, I drove to my car on my motorcycle, disconnected the battery for a few seconds, hooked it back up, and the engine ran fine. Drove back home, got on my bicycle, drove back to the car, put the bike inside and drove home.
I then bought my own scanner from China at a cost of 27$, free shipping. 6 months later, it happened again. Pulled over, plugged the scanner in, and read code P 2238, deleted it, and kept on going; that took 2 minutes
and no cost. That was 9 months ago; why is the TPS still going fine? I don't know, but by having my own reader, I've saved a lot of time and money.

I'm not telling anyone what to do if they get a CEL, but reading the code with your reader, and then deciding what to do about it, will save time, frustrations and money. You're just doing what someone else will do, but at a much lower cost. Even the cheap readers do a good job of reading codes, and telling you what it is.
I own a 2006 OB 3.0L, and 231,000KM. My wife has a 2010 Forester, and her own scanner also.
Cheers