wes878, your TCH was in stage 3. Stage 3 is when the TCH is warmed up, and as you coast down under 40 miles per hour the ICE stops. Stage 3 allows you to continue in EV mode until low SOC or acceleration restarts the ICE. Once restarted the ICE will run until you once again coast down under 40 miles per hour (coasting between 35 and 40mph enters stage 3)

Stage 4 is full hybrid mode. The only way I know of to enter stage 4 is to come to a stop for 7 to 10 seconds after the TCH is warmed up. Once in stage 4, anytime the SOC shows over 2 bars and you coast at any speed under 40mph, the ICE stops in 2 or 3 seconds. I've also entered stage 4 without a full stop, but was just barely creeping along at 2 or 3 miles per hour.

I believe stage 1 is the initial minute or so after the ICE first starts when the timing is retarded to rapidly heat up the cat converter. The ICE will shut off if you stop during stage 1. Stage 2 is the final warmup phase, and ICE will not stop until the coolant temps reach normal operating temperatures. This appears to be a little while after the temp gauge has reached it's normal reading.

Another behavior I have observed when stopping at a store for a short time, the TCH will go from stage 1 directly to stage 4 if I am slowly (5 to 15 miles per hour) driving or coasting after about 30 seconds.