| Table 1: | PCM Scan Tool Data List (LR4, LM7,LQ4) |
| Table 2: | PCM Scan Tool Data List (LU3) |
| Table 3: | ECM Scan Tool Data List For Auxiliary Coolant Heater (LLY) Diesel |
Use the Scan Tool Data Display Values and Definitions Information in order to assist in diagnosing the Powertrain Control Module (PCM) 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) | |||
A/C Compressor Cycling Switch | Engine Data 2 | Low Pressure/Normal | Normal |
A/C Relay Command | Engine Data 1 Engine Data 2 Misfire Data | On/Off | On |
A/C Request Signal | Engine Data 2 | 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 Compressor Cycling Switch | Engine Data 2 | Low Pressure/Normal | Normal |
A/C Relay Command | Engine Data 1 Engine Data 2 Misfire Data | On/Off | On |
A/C Request Signal | Engine Data 2 | Yes/No | Yes |
ECT | ALL | C/F | Varies |
Scan Tool Parameter | Data List | Units Displayed | Typical Data Value |
|---|---|---|---|
Operating Conditions: Engine running, ambient air temperature below 4°C (39°F) | |||
Ignition 1 signal | Auxiliary Heater Data Display | Volts | Battery Voltage |
Ambient Air Temperature | Auxiliary Heater Data Display | C/F | Varies |
Coolant Temp. Sensor | Auxiliary Heater Data Display | C/F | Varies |
Coolant Temp. Sensor | Auxiliary Heater Data Display | Volts | Varies |
Overheat Temperature Sensor | Auxiliary Heater Data Display | C/F | Varies |
Overheat Temperature Sensor | Auxiliary Heater Data Display | Volts | Varies |
Fuel Pump Command | Auxiliary Heater Data Display | On/Off | On |
Fuel Pump PWM | Auxiliary Heater Data Display | ms | Varies |
Desired Fuel Pump | Auxiliary Heater Data Display | ms | Varies |
Glow Plug Command | Auxiliary Heater Data Display | On/Off | On |
Glow Plug | Auxiliary Heater Data Display | % | Varies |
Glow Plug Sensor On | Auxiliary Heater Data Display | Volts | Varies |
Glow Plug Off | Auxiliary Heater Data Display | Volts | Varies |
Flame Detected | Auxiliary Heater Data Display | Yes/No | Yes |
Flame Temperature Sensor | Auxiliary Heater Data Display | Volts | Varies |
Flame Temperature Sensor | Auxiliary Heater Data Display | C/F | Varies |
Blower Motor Feedback Circuit | Auxiliary Heater Data Display | On/Off | On |
Desired Blower Motor | Auxiliary Heater Data Display | Volts | Varies |
Blower Motor | Auxiliary Heater Data Display | Volts | Varies |
System Voltage High | Auxiliary Heater Data Display | On/Off | Off |
System Voltage Low | Auxiliary Heater Data Display | On/Off | Off |
DTC Set This Ignition | Auxiliary Heater Data Display | Yes/No | No |
