| Subject: | Erratic Cruise Control Performance - Update ECM Calibration |
| Models: | 2007 Saturn Vue Greenline Hybrid |
| with 2.4L Engine (VIN Z - RPO LAT) |
| Manufactured before 12/10/2006 |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
On rare occasions, the following cruise control issues may be experienced with no DTCs stored:
| • | When pressing the "-" or cruise set switch, the transmission may downshift, causing the desired cruise control speed to overshoot by approximately 5 mph. After this occurs, the vehicle speed will drop to desired/normal set speed. |
| • | A "Bump" may be felt when driving in hills with the cruise control on. This "bump" occurs as the engine is making the transition from regeneration fuel cut mode on deceleration to acceleration with gasoline engine and electric assist. |
Recommendation/Instructions:
If the SI diagnostics do not isolate a cause for this concern, it is most likely the result of an ECM calibration issue. On 12/17/2006, an updated ECM calibration was released in TIS version 12.5 to address this concern. The title of this ECM calibration
is "enhanced cruise control performance". This calibration, or any that follow, is designed to address this concern. Vehicles manufactured after the breakpoint above should already contain this updated ECM calibration.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
