Use the Scan Tool Data Display Values and Definitions in order to assist in diagnosing the HVAC. Compare the vehicles actual scan tool data with the typical data display value table information. Use the data information in order to aid in understanding the nature of the concern when the vehicle does not match with the typical data display values.
The scan tool data values were taken from a known good vehicle under the following conditions:
| • | The ignition switch is in the ON position. |
| • | The engine is running at idle. |
| • | The vehicle is in PARK. |
| • | The doors are closed. |
| • | The windows are closed. |
| • | The A/C is ON. |
| • | The ambient air temperatures are at 22-27°C (70-80°F). |
Scan Tool Parameter | Data List | Units Displayed | Typical Data Value |
|---|---|---|---|
Body Control Module (BCM) Operating Conditions: Engine idling, A/C ON, ambient air temperature between 22-27°C (70-80°F) | |||
A/C Request Switch | Inputs | On/Off | Varies |
Engine Control Module (ECM) Operating Conditions: Engine idling, A/C ON, ambient air temperature between 22-27°C (70-80°F) | |||
A/C Disengage History 1, 2, 3, or 4 | Engine Data | None, A/C Pressure, Engine Speed, Batt Voltage, Anti Stall, RPM Unstable, WOT, Launch Perf., Coolant Hot | None |
A/C Pressure Disable | Engine Data | Yes/No | No |
A/C High Side Pressure Sensor | Engine Data | Volts | Varies |
A/C Off for WOT | Engine Data | Yes/No | Varies |
A/C Relay Circuit History | Engine Data | OK/Open/Short | OK |
A/C Relay Circuit Status | Engine Data | OK/Fault | OK |
A/C Relay Command | Engine Data | On/Off | Varies |
A/C Request Signal | Engine Data | Yes/No | Varies |
Ambient Air Temperature | Engine Data | °C/°F | Varies |
ECT Sensor | Engine Data | °C/°F | Varies |
Ignition 1 Signal | Engine Data | Volts | Varies |
A/C Disengage History 1, 2, 3, or 4 | Engine Data | None, A/C Pressure, Engine Speed, Batt Voltage, Anti Stall, RPM Unstable, WOT, Launch Perf., Coolant Hot | None |
A/C Pressure Disable | Engine Data | Yes/No | No |
A/C High Side Pressure Sensor | Engine Data | Volts | Varies |
