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Engine Controls - Scan Tool Displays Incorrect Values

01 07 30

Mar. 9, 2007

2014492





Affected Vehicles

Condition

Generic OBD II Scan Tool Displays Incorrect Values

Transmission Control Module (TCM) will report incorrect absolute load value (PID 43) in generic mode on any scan tool.

Technical Background

Two different absolute load values are observed when monitoring Service 1 and Service 2 in generic mode on any scan tool. The absolute load value is correctly reported by the ECM but is incorrectly reported by the TCM due to an incorrect scaling factor in the software.

The TCM Does Not use this value for diagnostics or control, therefore the incorrect reading poses no impact on the control or the operation of the vehicle. The absolute load value transmitted for the TCM is 40% to 60% lower than the correctly transmitted ECM absolute load value.

Tip:

There is a delay in the reported values from the TCM, in comparison to the ECM, due to the calculating capacity of the TCM. This delay is about 300 milliseconds during fast changes in load.

Production Solution

Software corrected for model year 2008.

Service

Note:
Do not replace the TCM or ECM for this condition. Monitor ECM values for correct values.

Warranty

Information only.

Required Parts and Tools

No Special Tools required.

No Special Parts required. Always see ETKA for the latest part(s) information.