1810016

Flash: Powertrain Diagnostic And System Enhancements This bulletin involves selectively erasing and reprogramming the Powertrain Control Module (PCM) with new software. A small number of customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the Technician may find that the following Diagnostic Trouble Codes have been set: U0140 - Lost Communication With Body Control Module (BCM) (12 MY DJ only) P0300 - Multiple Cylinder Misfire.The P0300 improvement only applies to vehicles using a block heater in ambient temperatures greater than -20°F(-29°C). P2008 - Short Runner Valve (SRV) Control Circuit. P1004 - Short Runner Valve Control Performance. P2016 - Intake Manifold Runner Position Sensor Circuit Low. P2017 - Intake Manifold Runner Position Sensor Circuit High. P0456 - Evap System Small Leak(applies only to vehicles equipped with a CNG engine): Excess gasoline mode operation under normal operating conditions (switching to gasoline mode too often). Slight hesitation on initial acceleration when starting in gasoline mode. Engine speed fluctuation on first gasoline to CNG mode transition under extremely low ambient temps.Also software enhancements were made to improve transmission durability.