Blower Delay Timer - HVAC System - Automatic

The blower delay timer is active only when the system senses it should be putting out heat in Heat Auto modes. The blower delay timer keeps the blower at minimum speed to allow the engine coolant to warm up. In cases of very cold ambient temperatures, delay can last up to 5 minutes. To check for correct operation of the blower delay timer:

^ Select 15°C (60°F) and Hi. No delay in system operation should occur.
^ Select a high temperature setting less then 32°C (90°F) in Auto mode. The blower delay timer should engage, keeping the blower at minimum speed (no longer than 5 minutes), until engine coolant has warmed up. Then, the blower fan should be energized.

In the Hi or Defrost modes or when cooling is required in Auto the blower delay timer will n0t function/nor should the timer function once the engine is warmed up. However there is a slow airflow ramp up when the vehicle is very hot.

The control must have a constant battery positive (+) feed to maintain memory function.