GM Service Manual Online
For 1990-2009 cars only
DDM -- Data Display -- Pass. HVAC Switch: The scan tool displays 0 to 255 counts. This indicates the passenger climate control selection.

DIM -- A/C Information -- A/C Clutch (Actual): The scan tool displays On or Off. On is displayed when the PCM has energized the A/C clutch relay.

DIM -- A/C Information -- A/C Clutch (Desired): The scan tool displays On or Off. On is displayed when the IPM is requesting A/C system operation and the DIM has determined that none of the system performance limits are exceeded.

DIM-- A/C Information --A/C Orifice Relay: The scan tool displays Active or Inactive. Active is displayed when the orifice tube relay is energized by the DIM increasing the orifice diameter and lowering A/C high side pressure.

DIM -- A/C Information -- A/C Pressure: The scan tool displays 0 to 4000 kPa (0 to 580 psi). The output of the A/C pressure sensor provided by the PCM over the Class 2 communication link.

DIM -- A/C Information -- Clutch Voltage: The scan tool displays Low or Normal. Low is displayed when the battery voltage is low, such that clutch slippage is possible.

DIM -- A/C Information -- Control Head (Desired): The scan tool displays A/C On or A/C Off. A/C On is displayed when the IPM is requesting A/C system operation.

DIM -- A/C Information -- Evaporator Temp.: The scan tool displays -40 to +215°C (-40 to +420°F). The output of the A/C low side thermistor.

DIM -- A/C Information -- Evaporator Temp Status: The scan tool displays OK or Cold. Cold is displayed when evaporator temperature drops below 5°C (41°F).

DIM -- A/C Information -- Pressure Status: The scan tool displays Low, Normal or High. Normal must be displayed to allow A/C operation.

DIM -- A/C Information -- Temperature Status: The scan tool displays Hot or OK. Hot is displayed when engine coolant temperature rises above 121°C (250°F). OK must be displayed to allow A/C operation.

IPM -- HVAC Sensors -- Outside Air Temp: The scan tool displays -40 to +60°C (-40 to +140°F). The output of the ambient air temperature sensor.

IPM -- HVAC Sensors -- Inside Air Temp: The scan tool displays -40 to +60°C (-40 to +140°F). The output of the inside air temperature sensor.

IPM -- HVAC Sensors -- Left AC Duct Temp: The scan tool displays -40 to +150°C (-40 to +300°F). The output of the LH A/C duct temperature sensor.

IPM -- HVAC Sensors -- Left HTR Duct Temp: The scan tool displays -40 to +150°C (-40 to +300°F). The output of the LH HTR duct temperature sensor.

IPM -- HVAC Sensors -- Right AC Duct Temp: The scan tool displays -40 to +150°C (-40 to +300°F). The output of the RH A/C duct temperature sensor.

IPM -- HVAC Sensors -- Right HTR Duct Temp: The scan tool displays -40 to +150°C (-40 to +300°F). The output of the RH HTR duct temperature sensor.

IPM -- HVAC Sensors -- Left Duct Temp Desired: The scan tool displays -18 to +120°C (0 to +250°F). The target LH A/C duct temperature that the HVAC system is trying to achieve.

IPM -- HVAC Sensors -- Right Duct Temp Desired: The scan tool displays -18 to +120°C (0 to +250°F). The target RH A/C duct temperature that the HVAC system is trying to achieve.

IPM -- HVAC Sensors -- Left Solar: The scan tool displays 0 to 50 counts. The solar load output of the LH sunload sensor and ambient light sensor.

IPM -- HVAC Sensor -- Right Solar: The scan tool displays 0 to 50 counts. The solar load output of the RH sunload sensor and ambient light sensor.

IPM -- HVAC System Data -- Commanded Blower: The scan tool displays 0 to 100%.

IPM -- HVAC System Data -- Selected Air Mode: The scan tool displays AUTO, Upper, Defog, Bi-Level, Heater or Defrost. The current operating mode of the HVAC system.

IPM -- HVAC System Data -- A/C Requested: The scan tool displays Yes or No. The message sent out on class 2 to the DIM when A/C is requested.

IPM -- HVAC System Data -- Coolant Temperature: The scan tool displays -40 to +120°C (-40 to +250°F). The information is received from the PCM on the class 2 communication link.

IPM -- HVAC Door Positions -- Left Temp. Dr. Commanded: The scan tool displays 0 to 255 counts (0 to 5 volts). The desired position of the actuator.

IPM -- HVAC Door Positions -- Left Temp Dr Actual: The scan tool displays 0 to 255 counts (0 to 5 volts). The signal output from the feedback pot on the actuator.

IPM -- HVAC Door Positions -- Right Temp. Dr. Commanded: The scan tool displays 0 to 255 counts (0 to 5 volts). The desired position of the actuator.

IPM -- HVAC Door Positions -- Right Temp Dr Actual: The scan tool displays 0 to 255 counts (0 to 5 volts). The signal output from the feedback pot on the actuator.

IPM -- HVAC Door Positions -- HTR/DEF/AC Dr Commanded: The scan tool displays 0 to 255 counts (0 to 5 volts). The desired position of the actuator.

IPM -- HVAC Door Positions -- HTR/DEF/AC Dr Actual: The scan tool displays 0 to 255 counts (0 to 5 volts). The signal output from the feedback pot on the actuator.

IPM -- HVAC Door Positions -- Air Inlet Dr Commanded: The scan tool displays 0 to 255 counts (0 to 5 volts). The desired position of the actuator.

IPM -- HVAC Door Positions -- Air Inlet Dr Actual: The scan tool displays 0 to 255 counts (0 to 5 volts). The signal output from the feedback pot on the actuator.

IPM -- HVAC Door Calibrations -- Min Left Temp Dr Pos: The scan tool displays 0 to 255 counts (0 to 5 volts). The minimum travel range when driven to the stop during Recalibrate All Motors command.

IPM -- HVAC Door Calibrations -- Max Left Temp Dr Pos: The scan tool displays 0 to 255 counts (0 to 5 volts). The maximum travel range when driven to the stop during Recalibrate All Motors command.

IPM -- HVAC Door Calibrations -- Min Right Temp Dr Pos: The scan tool displays 0 to 255 counts (0 to 5 volts). The minimum travel range when driven to the stop during Recalibrate All Motors command.

IPM -- HVAC Door Calibrations -- Max Right Temp Dr Pos: The scan tool displays 0 to 255 counts (0 to 5 volts). The maximum travel range when driven to the stop during Recalibrate All Motors command.

IPM -- HVAC Door Calibrations -- Min HTR/DEF/AC Dr Pos: The scan tool displays 0 to 255 counts (0 to 5 volts). The minimum travel range when driven to the stop during Recalibrate All Motors command.

IPM -- HVAC Door Calibrations -- Max HTR/DEF/AC Dr Pos: The scan tool displays 0 to 255 counts (0 to 5 volts). The maximum travel range when driven to the stop during Recalibrate All Motors command.

IPM -- HVAC Door Calibrations -- Min Air Inlet Dr Pos: The scan tool displays 0 to 255 counts (0 to 5 volts). The minimum travel range when driven to the stop during Recalibrate All Motors command.

IPM -- HVAC Door Calibrations -- Max Air Inlet Dr Pos: The scan tool displays 0 to 255 counts (0 to 5 volts). The maximum travel range when driven to the stop during Recalibrate All Motors command.

IPM -- Open/Short Data -- Outside Air Temp: The scan tool displays 0 to 255 counts (0 to 5 volts). The status of the sensor signal circuit is monitored. 0 counts indicates a short to ground, 255 counts indicates an open circuit.

IPM -- Open/Short Data -- Inside Air Temp: The scan tool displays 0 to 255 counts (0 to 5 volts). The status of the sensor signal circuit is monitored. 0 counts indicates a short to ground, 255 counts indicates an open circuit.

IPM -- Open/Short Data -- Left AC Duct Temp: The scan tool displays 0 to 255 counts (0 to 5 volts). The status of the sensor signal circuit is monitored. 0 counts indicates a short to ground, 255 counts indicates an open circuit.

IPM -- Open/Short Data -- Left HTR Duct Temp: The scan tool displays 0 to 255 counts (0 to 5 volts). The status of the sensor signal circuit is monitored. 0 counts indicates a short to ground, 255 counts indicates an open circuit.

IPM -- Open/Short Data -- Right AC Duct Temp: The scan tool displays 0 to 255 counts (0 to 5 volts). The status of the sensor signal circuit is monitored. 0 counts indicates a short to ground, 255 counts indicates an open circuit.

IPM -- Open/Short Data -- Right HTR Duct Temp: The scan tool displays 0 to 255 counts (0 to 5 volts). The status of the sensor signal circuit is monitored. 0 counts indicates a short to ground, 255 counts indicates an open circuit.

IPM -- Open/Short Data -- Left Solar Sensor: The scan tool displays 0 to 50 counts. The status of the sensor signal circuit is monitored. 0 counts indicates a short to ground, 255 counts indicates an open circuit.

IPM -- Open/Short Data -- Right Solar Sensor: The scan tool displays 0 to 50 counts. The status of the sensor signal circuit is monitored. 0 counts indicates a short to ground, 255 counts indicates an open circuit.

PCM -- Engine Data 1 w/LX5 (V6)-- ECT: The scan tool displays -40 to +215°C (-40 to +420°F). The output of the engine coolant temperature sensor.

PCM -- Engine Data 2 w/LX5 (V6) -- A/C Request Signal: The scan tool displays Yes or No. Yes is displayed when the DIM is requesting A/C system operation.

PCM -- Engine Data 2 w/LX5 (V6) -- A/C Relay Command: The scan tool displays On or Off. On is displayed when the PCM has energized the A/C clutch relay.

PCM -- Engine Data 2 w/LX5 (V6) -- A/C High Side Pressure: The scan tool displays 0 to 4000 kPa (0 to 580 psi). The output of the A/C pressure sensor.

PCM -- Engine Data 2 w/LX5 (V6) -- A/C High Side Pressure: The scan tool displays 0 to 5 volts. The output of the A/C pressure sensor.

PCM -- Engine Data 2 w/LX5 (V6) -- A/C Off for WOT: The scan tool displays Yes or No. Yes is displayed when the PCM denergizes the A/C CLU relay to reduce engine load during application wide open throttle.

PCM -- Engine Data 2 w/LX5 (V6) -- A/C Pressure Disable: The scan tool displays Yes or No. Yes is displayed when the system pressure exceeds 2968 kPa (430 psi).

PCM -- Engine Output Controls w/LX5 (V6) -- A/C Relay: The scan tool displays OK or Fault. Fault is displayed when an open or short is detected in the A/C CLU relay ground circuit.

PCM -- Engine Data 1 w/L47 (V8)-- ECT: The scan tool displays -40 to +215°C (-40 to +420°F). The output of the engine coolant temperature sensor.

PCM -- Engine Data List 1 w/LX5 (V6) -- A/C Relay Command: The scan tool displays On or Off. On is displayed when the PCM has energized the A/C clutch relay.

PCM -- Engine Data 2 w/L47 (V8)-- ECT: The scan tool displays -40 to +215°C (-40 to +420°F). The output of the engine coolant temperature sensor.

PCM -- Engine Data 2 w/L47 (V8) -- A/C Relay Command: The scan tool displays On or Off. On is displayed when the PCM has energized the A/C clutch relay.

PCM -- Engine Data 3 w/L47 (V8)-- ECT: The scan tool displays -40 to +215°C (-40 to +420°F). The output of the engine coolant temperature sensor.

PCM -- Engine Data 1 w/L47 (V8)-- A/C Relay Command: The scan tool displays ON or OFF. ON is displayed when the PCM has energized the A/C clutch relay.

PCM -- Engine Data 2 w/L47 (V8)-- A/C High Side Pressure: The scan tool displays 0 to 4000 kPa (430 psi). The output of the A/C pressure sensor.

PCM -- Engine Data 3 w/L47 (V8)-- A/C Relay Command: The scan tool displays ON or OFF. ON is displayed when the PCM has energized the A/C clutch relay.

PCM -- Engine Output Controls w/L47 (V8)-- A/C Relay: The scan tool displays OK or Fault. Fault is displayed when an open or short is detected in the A/C CLU relay ground circuit.