This Preliminary Information communication provides information to the technician about vehicles that during battery parasitic drain test, there may be some confusion as to what the normal power consumption reading should be from the OnStar system. Technician should understand the power cycles of the various OnStar systems. All Generation 6, 7, 8, and 9 systems are powered up continuously for 48 hours from ignition off. After 120 hours from ignition off, these systems then completely power off.
The Onstar modules draw:
* IGN ON - 240 to 400 Milliamp.
* IGN OFF - 3 to 20 Milliamp for 48 hours or 120 hours on Gen 9 and vehicle communication
* IGN OFF - 0.2 to 0.8 Milliamp after 48 hours or 120 hours on Gen 9 and vehicle communication