Subject: | No ISS Signal at Low Speeds |
Models: | 2007-2009 Chevrolet Colbalt, Malibu, HHR |
2007-2009 Pontiac G5, G6 |
2007-2009 Saturn Aura, Ion, Vue |
equipped with 4T45E transmission (RPOs MN5, ME7) |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Recently several cases have surfaced where DTC P0717 sets and there is no ISS signal until 38 mph or 1800-2000 rpm.
If the air gap and resistence checks are ok, but concern continures. The cause may be the internal trans wiring harness has been chaffed by a sharp edge on a hold down clip and is grounding out until sufficient vibration at higher RPM's interrupts the ground out. Checking 20 Way Connector pins 'S' and 'V' to ground may show some resistence readings when there should be none. For this condition (no ISS until higher RPM) , replace the transmission internal wiring harness. This applies to both RPO's: MN5, ME7.
For pin out locations see SI Doc 1887360, connector #11 (engine to transmission).
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.