Up to yesterday, PMDG B-777 Auto Cruise was working perfectly, but now, in spite of flying straight and level at a constant speed, I cannot make it engage.

I have tried using both the method of right-clicking on the clock and also setting AUTO TIME COMPRESSION to 'ON' in the FMC. Neither of these will turn on Auto Cruise.

Any ideas, anyone?

The use to the term "auto cruise" could be misleading.  The speed control in a car is often call auto cruise.  Back on topic, your problem is auto time compression, right?  What is the maximum rate that you have selected? It will do x16 but I find anything over x4 is overkilling it.  What about weather?  If there are gusts/variable winds and the typical very unrealistic weather generation in FSX/P3D that will inhibit the auto time compression from kicking in.

Thanks, downscc, for your reply.

To answer your points:-

1. "Auto Cruise" is the term used in Tutorial _1.

2, Yes, it's "AUTO TIME COMPRESSION" on the Auto Cruise page of the FMC.

3. I have selected the rate of x4.

4. Weather is stable with a tail jet stream of 167 knots.

But I have found the answer... I went back to the Auto Cruise page and clicked on  RESET and Hey Presto! Auto Cruise engaged. I have never encountered this before and I've used the process many times on other long flights.

Sorry to have troubled you. Perhaps this thread will help someone else with the same problem.

Regards,

Mark

Well, okay...., I guess Ryan had cruisin' in mind when he wrote the Intro and Tutorial. No biggy.

I am glad you posted the solution. I've never have had to use the RESET on the .... oh wait, just realized they call that page AUTO CRUISE because it deals with auto time compression, auto step climb and auto pause before descent.  Okay, I just couldn't get the right context earlier.

Thanks for posting the solution.