This bulletin applies to a range of Dodge Ram 4x4 trucks equipped with an electronic transfer case and built before Jan. 6, 2012, where the “Service 4WD” light is illuminated and the DTCM requires reprogramming.
This bulletin applies to 1996-2009 Isuzu Ascender 4WD vehicles. Issues may involve poor acceleration, detonation ping at idle in drive or reverse, and/or possible DTC P0101, P0106 and/or P0121 set in the PCM. The vehicle will perform properly after attaining a speed of about 30-40 mph.
Some owners of 2004-2012 Chevy Colorado 4WD trucks may comment on a “Service 4 Wheel Drive” message displayed in the DIC (driver’s information center). Technicians may find DTC C0327 stored in current or history in the TCCM.
Owners of a 2012 Dodge Ram 3500 equipped with an electronic transfer case and built before Jan. 6, 2012, may see a “Service 4WD” light in the cabin compartment node. The technician may find that C2201 (FDCM/DTCM internal diagnostic trouble code) is set in the DTCM. When the system detects this, it shuts down the 4WD capability for the remainder of the drive cycle.
This bulletin applies to 2014 Jeep Grand Cherokee vehicles equipped with the Quadra-Trac II 4WD system or two Speed On Demand Transfer Case. The owner may comment about a bump felt in the driveline while turning from a stop.
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