GM Service Manual Online
For 1990-2009 cars only

Scan Tool Output Control

Additional Menu Selection(s)

Description

A/C Relay

Engine Output Controls/A/C Relay

Activates the A/C compressor relay. The normal commanded state of the A/C relay is NONE.

A/C LED

Body/BCM/A/C LED

Activates the A/C LED indicator. The normal commanded state of the A/C LED is OFF.

Cooling Fan

Engine Output Controls / Cooling Fan

Activates the cooling fan 1 by enabling the fan relay 1. The normal commanded state of the relay is NONE. The ECM allows relay control when the following conditions are met:

    • The transmission must be in Park or Neutral.
    • The A/C request is OFF.
    • The engine coolant temperature is less than 100°C (212°F).
    • No vehicle speed is detected

Fan Relay 1

Engine Output Controls / Fan Relays

Activates the cooling the fan 1 by enabling fan relay 1. The normal commanded state of the relay is NONE. The PCM allows relay control when the following conditions are met:

    • The transmission must be in Park or Neutral.
    • The A/C request is OFF.
    • The engine coolant temperature is less than 100°C (212°F).
    • No vehicle speed is detected

Fan Relays 2 and 3

Engine Output Controls / Fan Relays

Activates the cooling fan 2 by enabling fan relay 2. The normal commanded state of the relay is NONE. The PCM allows relay control when the following conditions are met:

    • The transmission must be in Park or Neutral.
    • The A/C request is OFF.
    • The engine coolant temperature is less than 100°C (212°F).
    • No vehicle speed is detected

Fan Relays 1, 2 and 3

Engine Output Controls / Fan Relays

Activates the cooling fan 2 by enabling fan relay 2. The normal commanded state of the relay is NONE. The PCM allows relay control when the following conditions are met:

    • The transmission must be in Park or Neutral.
    • The A/C request is OFF.
    • The engine coolant temperature is less than 100°C (212°F).
    • No vehicle speed is detected