NOTE: This information applies to vehicles equipped with gasoline engines built prior to December 18, 1998 (MDH 1218XX).
Some vehicles may exhibit an idle undershoot or die out during engine starting and may be caused by IAC lost steps. This condition is more likely to occur during cold weather, low battery voltage, cold engine start, and quick ignition key "On" - "Off" operation.
Using the Mopar Diagnostic System (MDS/MDS2) or the Diagnostic Scan Tool (DRB III) with the appropriate Diagnostic Procedures Manual, verify all engine/transmission systems are functioning as designed. If Diagnostic Trouble Codes (DTC's) are present, record them on the repair order and repair as necessary before proceeding further with this bulletin. If no other problems are found,
This procedure involves selectively erasing and reprogramming the Powertrain Control Module (PCM) with new software (99cal14 calibration change).
1. Connect the MDS (Mopar Diagnostic System) and DRB III (Scan Tool) to the vehicle and power them up. 2. Use the arrow keys and select #2 CONNECT TO MDS 1 OR MDS 2 on the DRB III MAIN MENU Screen. 3. Select #1 MDS DIAGNOSTICS OR DRB UPDATE on the DRB III. 4. Use the arrow keys and select DIAGNOSTIC MENU on the MDS, then press NEXT MENU. 5. Use the arrow keys and select VEHICLE CONTROLLER PROGRAMMING on the MDS, then press NEXT MENU. 6. Use the arrow keys and select PROGRAMMING OF ALL OTHER CONTROLLERS USING MDS & DRB III on the MDS, then press NEXT MENU. 7. Follow the steps presented on the MDS and DRB III which will allow the DRB III to obtain the current part number of the PCM. 8. The MDS will display the part number of the PCM on the vehicle and the appropriate replacement part number, then press NEXT MENU to begin programming.
If the PCM on the vehicle has already been updated or programmed, a NO UPDATES AVAILABLE message will be displayed. Check the part number of the PCM on the vehicle
and compare it to the part number displayed. If the PCM has already been updated, then another condition exists that will require further diagnosis and repair.
9. The MDS and DRB III will prompt for any operator action needed during the remainder of the programming process.
NOTE: XJ vehicles equipped with an Aisin Warner transmission may set DTC $BE (CCD Message From JTEC Failure) within the TCM because of the flash procedure and the DTC logged in the TCM may set DTC $89 (TCM Controller DTC Present) within the PCM. Check for and erase these DTC's prior to returning the vehicle to the customer.
NOTE: The following steps are required by law.
10. Type the necessary information on the "Authorized Software Update Label" p/n 04669020 Attach the label to the PCM and cover the label with the clear plastic overlay. 11. Type the necessary information on the "Authorized Modification Label" p/n 04275086 and attach the label near the VECI Label
Monday, December 15th, 2008 AT 6:11 AM