Final answer:
The blue air hose connects to the emergency (blue) coupling, and the red air hose connects to the service (red) coupling on the M983 series HEMTT.
Step-by-step explanation:
On the M983 series HEMTT, the blue air hose connects to the emergency (blue) coupling and the red air hose connects to the service (red) coupling. The correct coupling locations are typically standardized across most pneumatic systems, where blue is for emergency and red is for service functions. By following this convention, the system ensures proper connection for vehicle operations and safety.