| Table 1: | HVAC Control Module Scan Tool Data List |
| Table 2: | Powertrain Control Module (PCM) Scan Tool Data List (L61) |
| Table 3: | Engine Control Module (ECM) Scan Tool Data List (L81) |
Use the Scan Tool Data Display Values and Definitions Information in order to assist in diagnosing the HVAC Control Module problems. 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 problem 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 |
|---|---|---|---|
Operating Conditions: Engine idling, A/C ON, ambient air temperature between 22-27°C (70-80°F) | |||
Auto Switch - Actual | Defrost/Actuator Data | High/Low | Varies |
Auto Switch Cmd | Actuator Data | On/Off | Varies |
Defrost Switch - Actual | Defrost Data | High/Low | Varies |
Defrost Switch Cmd | Defrost Data | On/Off | Varies |
Defrost LED | Defrost Data | On/Off | Varies |
Economy Switch - Actual | Defrost/Actuator Data | High/Low | Varies |
Economy Switch Cmd | Actuator Data | On/Off | Varies |
Fan Speed | Defrost/Actuator Data | Counts | Varies |
Mix Fdbk | Actuator Data | Counts | Varies |
Mode Switch - Actual | Actuator Data | High/Low | Varies |
Mode Switch Cmd | Actuator Data | On/Off | Varies |
Mode Fdbk | Actuator Data | Counts | Varies |
Off Switch - Actual | Defrost/Actuator Data | High/Low | Varies |
Off Switch Cmd | Actuator Data | On/Off | Varies |
Outside Air Temp | Defrost/Actuator Data | Counts | Varies |
Psgr. Compartment Temp | Defrost/Actuator Data | Counts | Varies |
Rear Defrost Switch - Actual | Defrost Data | High/ Low | Varies |
Rear Defrost Switch Cmd | Defrost Data | On/Off | Varies |
Rear Defrost Fdbk | Defrost Data | High/ Low | Varies |
Recirc LED | Actuator Data | On/Off | Varies |
Recirc Switch - Actual | Actuator Data | High/Low | Varies |
Recirc Switch Cmd | Actuator Data | On/Off | Varies |
Solar Sensor | Defrost/Actuator Data | Counts | Varies |
Scan Tool Parameter | Data List | Units Displayed | Typical Data Value |
|---|---|---|---|
Operating Conditions: Engine idling, A/C ON, ambient air temperature between 22-27°C (70-80°F) | |||
A/C High Side Pressure | General Info-Inputs | kPa/psi | Varies |
A/C High Side Pressure | General Info-Inputs/Outputs | 0 to 5 Volts | Varies |
A/C Relay Command | General Info-Inputs/Outputs | On/Off | On |
A/C Relay Circuit Open or Short to Ground | General Info-Outputs | Yes/No | No |
A/C Relay Circuit Short to Volts | General Info-Outputs | Yes/No | No |
A/C Request | General Info-Inputs/Outputs | Yes/No | Yes |
ECT | All | C/F | Varies |
Scan Tool Parameter | Data List | Units Displayed | Typical Data Value |
|---|---|---|---|
Operating Conditions: Engine idling, A/C ON, ambient air temperature between 22-27°C (70-80°F) | |||
A/C High Side Pressure | General Info-Inputs | kPa/psi | Varies |
A/C High Side Pressure | General Info-Outputs | 0 to 5 Volts | Varies |
A/C Relay Command | General Info-Inputs/Outputs | On/Off | On |
A/C Request | General Info-Inputs | Yes/No | Yes |
ECT | All | C/F | Varies |
