GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2008 🢒 SLS 🢒 HVAC 🢒 HVAC - Automatic 🢒 Afterblow Enabling

The following conditions must be met for afterblow to operate:

    • The engine has been turned off for at least 30 minutes.
    • The ambient air temperature is at least 21°C (70°F).
    • The A/C compressor operated for more than 2 minutes.
    • The system voltage is at least 12 volts.

Once the above conditions have been met, the following sequence of events will occur:

  1. The blower motor will run for 20 seconds.
  2. The blower motor will be off for 10 minutes.
  3. The blower motor will run for and additional 20 seconds.