PHOENIX - A Phoenix man has pleaded not guilty to murder and abuse charges stemming from the September death of his 1-year-old son .
The boy had been left in a hot car while the father went to work.
A Maricopa County Superior Court spokeswoman says Brokale Lytte Marques entered his plea Wednesday.
Marques was arrested after his son was found at a Scottsdale mall parking lot in a lethargic state.
Authorities say Marques told investigators he left the baby in a car seat because he was unable to find a sitter.
Marques told investigators he initially left the vehicle running and the air conditioning on, but later turned it off.
The boy died later at a hospital.