The scan tool used provides the following capabilities:
| • | Displays the data list. |
| • | Displays current and history trouble codes. |
| • | Clear the diagnostic trouble codes after a repair is completed. |
Important: Make sure the scan tool that you are using is functioning properly and has the latest software. Use of a malfunctioning scan tool or one that has old software can result in misdiagnosis and unnecessary parts replacement.
To use the scan tool, connect it to the data link connector (DLC) and turn the ignition switch to the RUN position.
The Transfer Case Scan Tool Data List contains all the automatic transfer case (ATC) related parameters that are available on the scan tool. The scan tool data list is arranged in alphanumeric order.
Use the Transfer Case Scan Tool Data List only after the following is determined:
| • | A Diagnostic System Check has been completed. |
| • | No diagnostic trouble codes (DTCs) are set. |
| • | Transfer Case Diagnostics indicates the system is functioning properly. |
Scan tool values from a properly operating system may be used for comparison with the transfer case system you are diagnosing. The Transfer Case Scan Tool Data List represents values recorded under the following conditions:
| • | Engine is at idle |
| • | Closed throttle |
| • | Gear is in PARK or NEUTRAL |
| • | Accessories are OFF |
Only the parameters listed below are referenced in this service manual for use in diagnosis. If all values are within the typical range described below, diagnose the problem using Intermittents and Poor Connections.
Engine is at Idle, Upper Radiator Hose Hot, Closed Throttle, Gear is in Park or Neutral, and Accessories are OFF. | |||
|---|---|---|---|
Scan Tool Parameter | Data List | Units Displayed | Typical Data Value |
ATC Slip Speed | Data Display | RPM | 0 |
AWD Enabled | Data Display | Yes/No | No |
AWD Lamp Open | Data Display | Yes/No | No |
AWD Lamp Shorted | Data Display | Yes/No | No |
Front Propshaft Signal Fault | Data Display | Yes/No | No |
Front Propshaft Speed | Data Display | RPM | 0 |
GM Part Number | Data Display | Number | Varies |
Ignition 3 | Data Display | Volts | Battery Positive Voltage |
Last Adapt Highest PWM | Data Display | %DC | Varies |
Motor Ground Circuit Open | Data Display | Yes/No | No |
Motor A or B Circuit Fault | Data Display | Yes/No | No |
Motor A or B Shorted to Gnd. | Data Display | Yes/No | No |
Motor A or B Shorted to Volts | Data Display | Yes/No | No |
Rear Propshaft Signal Fault | Data Display | Yes/No | No |
Rear Propshaft Speed | Data Display | RPM | 0 |
Slip Adapt PWM | Data Display | %DC | 0 |
Software ID | Data Display | Number | Varies |
TP Angle | Data Display | % | 0 |
