| Subject: | Harsh Shifts, MIL Illuminated, DTC P0717 Input Speed Sensor (ISS) Circuit Low Voltage |
| Models: | 2006-2007 Buick Rainier |
| 2006-2007 Chevrolet Trailblazer |
| 2007 Chevrolet Avalanche, Colorado, Silverado, Suburban, Tahoe |
| 2007 GMC Canyon, Sierra, Yukon, Yukon XL |
| Equipped with 4L60E or 4L70E Automatic Transmission (RPO M30 or M70) |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Some customers may comment on a harsh shift, illuminated MIL and a DTC P0717 may be found as a history code in the TCM.
Recommendation/Instructions:
If diagnosis of this condition leads to removal of the pump and ISS it is important to visually inspect the condition of the ISS wires. These wires can be damaged in the area where they exposed and not encased in conduit as shown in the figure below.
WPC returns have shown that when wire damage has occurred it is usually the white wire that is damaged. If wire damage is found replace the ISS and inspect the pump cover in same area for any possible sharp points that may cause damage to the wire. Any sharp
points on the pump casting in this area should be removed with a file.
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.
