Grand Cherokee 2WD V6-3.7L (2008)
Control Module: All Technical Service Bulletins
Engine Controls - MIL ON/DTC's P0730/P0731
NUMBER: 18-007-10
GROUP: Vehicle Performance
DATE: March 20, 2010
THE wiTECH DIAGNOSTIC APPLICATION IS THE PREFERRED METHOD FOR FLASHING ECUs. HELP USING THE wiTECH
DIAGNOSTIC APPLICATION FOR FLASHING AN ECU IS AVAILABLE BY SELECTING "HELP" THEN "HELP CONTENTS" AT THE TOP
OF THE wiTECH DIAGNOSTIC APPLICATION WINDOW.
THE wiTECH SOFTWARE LEVEL MUST BE AT RELEASE 10.02 OR HIGHER TO PERFORM THIS PROCEDURE.
StarMOBILE DESKTOP CLIENT or StarSCAN MAY ALSO BE USED TO PERFORM THIS PROCEDURE.
SUBJECT:
Flash: MIL Illumination P0730 And/Or P0731 And Fuel Economy Improvement
OVERVIEW:
This bulletin involves selectively erasing and reprogramming both the Powertrain Control Module (PCM) and Transmission Control Module (TCM)
with new software.
MODELS:
2008
(WK)
Grand Cherokee
2008
(WH)
Grand Cherokee (International Markets)
2008
(XK)
Commander
NOTE:
This bulletin applies to all vehicles equipped with a 3.7L engine (Sales code EKG) and a NAGI transmission (Sales code DGJ).
SYMPTOM/CONDITION:
The customer may experience a MIL illumination (4WD or AWD models only) with one or both of the following Diagnostic Trouble Codes (DTC)
when accelerating on slick road surface and experiencing momentary wheel slippage:
1. P0730 - Incorrect Gear Ratio
2. P0731 - Gear Ratio Error in 1st
This Software also gives a fuel economy improvement for all WK/WH/XK vehicles. The software now has a interactive fuel shut off strategy and the
optimization of TCM shift and torque converter clutch lock up/unlock schedules. This improvement could be as much as +0.5 MPG in city driving
conditions. Not all vehicles will realize a improvement due to driving habits and optional equipment that may have been installed on the vehicle.
DIAGNOSIS:
Using a Scan Tool (wiTECH(TM)) with the appropriate Diagnostic Procedures available in TechCONNECT, verify all engine and transmission Systems
are functioning as designed. If DTC's are present other then the one's listed above record them on the repair order and repair as necessary before
proceeding further with this bulletin.
If the above condition is present, perform the Repair Procedure.
PARTS REQUIRED:
REPAIR PROCEDURE:
NOTE: