"FLASH: POWERTRAIN DIAGNOSTIC AND SYSTEM IMPROVEMENTS
THIS BULLETIN INVOLVES REPROGRAMMING THE POWERTRAIN CONTROL MODULE (PCM) WITH UPDATED
SOFTWARE.
THE TECHNICIAN MAY FIND THE FOLLOWING DIAGNOSTIC TROUBLE CODE (DTC) SET IN THE POWERTRAIN
CONTROL MODULE (PCM) MEMORY:
· **U0140 - LOST COMMUNICATION WITH BODY CONTROL MODULE.**
SOME CUSTOMERS MAY EXPERIENCE ANY OF THE FOLLOWING:
· **2 - 1 DOWNSHIFT CLUNK OR BUMP (JC VEHICLES).**
· LONG CRANK TIMES WHEN TEMPERATURE IS BETWEEN -6°C AND -3°C (20°F AND 25°F) AND
15°C AND 18°C (60°F AND 65°F).
· ENGINE RPM FLUCTUATION ON CLOSED THROTTLE DECELERATION BETWEEN 48 KPH AND 32
KPH (30 MPH AND 20 MPH).
· SLIGHTLY ELEVATED RPM (100 RPM) WHILE DRIVING SLOW OR PARKING LOT DRIVING CONDITIONS
(JC VEHICLES).
UPDATING THE PCM SOFTWARE WILL CORRECT THE CONDITIONS LISTED ABOVE."
