Both Uses of

recede
in
All the Pretty Horses

[He] watched the small red taillight recede down the street and out toward the highway leaving him alone in the darkened town.
Chpt 4 *

recede = move away

The fire in the tank behind them was invisible save for the play of it on the rocks of the rincon and as they rode it receded to a faint glow pocketed in the otherwise dark of the desert night and then vanished altogether.†
Chpt 4

receded = move away or diminished (became less)

Definition:

to move away or diminish (become less)

The exact meaning of recede depends upon its context. For example:

"We can't move back in until the floodwaters recede." -- diminish and move away
"Her fear receded." -- diminished
"The waves first advance and then recede." -- move away
"The news story receded into the background as it was replaced by new stories." -- received diminished attention
"a receding hairline" -- diminished hair (each year the line where hair stops growing is higher on the forehead)
"She has a receding chin." -- sloping back (as contrasted to sticking out)