Engine Controls - Clunk/Shudder On Cruise Control Resume/WOT

NUMBER: 18-010-12

GROUP: Vehicle Performance

DATE: March 13, 2012

THIS BULLETIN SUPERSEDES SERVICE BULLETIN 18-038-11 REV. A, DATED OCTOBER 18, 2011, WHICH SHOULD BE REMOVED FROM YOUR FILES. ALL REVISIONS ARE HIGHLIGHTED WITH **ASTERISKS** AND INCLUDE THE ADDITION OF 2009 4.7L VEHICLES.

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 12.02 OR HIGHER TO PERFORM THIS PROCEDURE.

SUBJECT:
Flash: Clunk And Shudder Felt When Resuming Speed With Cruise Control Or On Wide Open Throttle Event

OVERVIEW:
This bulletin involves flash reprogramming the Powertrain Control Module (PCM) with new software.

MODELS:

**2009**~2010 (WK) Grand Cherokee

**2009**~2010 (WH) Grand Cherokee

**2009** - 2010 (XK) Commander

**2009** - 2010 (XH) Commander

NOTE:
This Service Bulletin applies to 2009 and 2010 vehicles equipped with a 5.7L engine (Sales Code EZH or EZD) and a 545RFE transmission (Sales Code DGQ) or **2009 vehicles equipped with a 4.7L engine (Sales Code EVA) and a 545RFE transmission (Sales Code DGQ)**.

SYMPTOM/CONDITION:
Some customers may notice any of the following:

I. A Clunk sound or feel a shudder when the cruise control resume switch is pressed. This condition is most noticeable after the brakes were pressed to cancel cruise control and then the resume switch is pressed.

II. A shudder or shaking feeling when a wide open throttle (WOT) event is performed by the customer. This is most noticeable after the transmission downshifts during the WOT event. This condition will stop once the transmission upshifts.

The PCM software has been updated to accommodate this condition.

DIAGNOSIS:
Using a Scan Tool (wiTECH(TM)) with the appropriate Diagnostic Procedures available in TechCONNECT, verify no DTC's are set. If DTC's are present record them on the repair order and repair as necessary before proceeding further with this bulletin.

If the customer describes any of the symptoms, perform the Repair Procedure.





PARTS REQUIRED:

REPAIR PROCEDURE:

NOTE:
Install a battery charger to ensure battery voltage does not drop below 13.2 volts. Do not allow the charging voltage to climb above 13.5 volts during the flash process.

NOTE:
If this flash process is interrupted/aborted, the flash should be restarted.

1. Reprogram the PCM with the latest software. 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.

2. After PCM reprogramming, the following must be performed: Clear any DTC's that may have been set in other modules due to reprogramming. The wiTECH application will automatically present all DTCs after the flash and allow the tech to clear them.

3. Type the necessary information on the "Authorized Modification Label" and attach it near the VECI label.

POLICY:
Reimbursable within the provisions of the warranty.





TIME ALLOWANCE:





FAILURE CODE:

Disclaimer:
This bulletin is supplied as technical information only and is not an authorization for repair.