30/2008 High readings of the temperature gauge when driving uphill or towing trailer especially under warm ambient temp.
Should a customer express concern about high readings of the temp guage when driving as described above the probable cause is a non robust communication between the powertrain PCM and the instrument cluster IC Subsequently the IC software interpretes the calculated engine coolant temp signal from the PCM wrongly. This TSB is only valid for vehicles built from 12/2006 up to 16/04/2007. Performing this TSB on vehicles built before 12/2006 could lead to damages to the PCM. IDS units with IDS 854 or 855 installations must be updated via the service network to action this TSB. The required IDS level to action this TSB is 856 and later. To rectify this concern, THE PCM must be re-programmed with the latest PCM configuration. The new calibration lets the PCM send a revised ECT signal via the CAN-bus wghich is compatible again with the IC software allowing correct reading.You can trim a sheeps wool many times, but you can only fleece it once !