Robert,
Got to tell ya, even when mine is fully charged and all the green lights on, if I am not running trains or switches with it, the Cab2 sits in the powered 990 charging station. However on initial charging, my Cab2 took several hours and I fially had to take the Cab2 out of the Legacy base, per Guns (John's) instructions, and re-insert it before the green lights finally came on blinking and eventually went solid Green. If you have not done it, take your Cab2 out of the base unit, try using it a little, then set it back in your 990 base for a while and the red blinking lights should eventually blink Green.
PCRR/Dave