PCM - Loss of Communications With Scan Tool
NUMBER: 08-39-99GROUP: Electrical
EFFECTIVE DATE: Dec. 10,1999
SUBJECT:
Communications May Stop Between the JTEC PCM and a Generic Scan Tool
OVERVIEW:
This bulletin involves selectively erasing and reprogramming the JIEC Powertrain Control Module (PCM) with new software (calibration change OOCal13 & OOCal13A).
MODELS:
2000 (AB) Ram Van
2000 (AN) Dakota
2000 (BR/BE) Ram Truck
2000 (DN) Durango
2000 (TJ) Wrangler
2000 (XJ) Cherokee
2000 (WJ) Grand Cherokee
NOTE:
THIS INFORMATION APPLIES TO VEHICLES BUILT BEFORE NOVEMBER 30, 1999 (MDH 113OXX).
SYMPTOM/CONDITION:
The JTEC Powertrain Control Module (PCM) may stop communications with a generic scan tool. It may appear that the sensor values are not updating on the generic scan tool screen. This condition may occur at any time during communications between the PCM and Generic Scan Tool. The condition will only occur if a Generic Scan Tool is used to communicate with the PCM, or if the DRB III is used to communicate with the PCM while it is in its generic scan tool mode. If the condition occurs while the DRB III is being used in its generic scan tool mode, a "No Response" message will occur.
If the condition occurs, the technician may have to restart initial communications with the PCM in order to continue with their diagnosis.
DIAGNOSIS:
Using the Mopar Diagnostic System (MDS2) and 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 DTC's are present, and the above symptoms have been experienced, perform the Repair Procedure.
NOTE:
WHENEVER A POWERTRAIN CONTROL MODULE (PCM) IS REPLACED DUE TO FAILURE, THE SOFTWARE OF THE REPLACEMENT CONTROLLER MUST BE VERIFIED FOR THE LATEST REVISION LEVEL. USE THE FLASH PROCEDURE TO UPDATE REPLACED CONTROLLERS AS NECESSARY.
PARTS REQUIRED:
1 04669020 Label, Authorized Software Update
1 04275086 Label, Authorized Modification
EQUIPMENT REQUIRED:
1 CH6000 Scan Tool (DRB III)
1 CH7035 General Purpose Interface Bus Cable (GPIB)
1 CH7000/7001 Jl962CabIe
1 MDS2
NOTE:
THE MDS2 AND DRB III ARE REQUIRED TO PERFORM PART OF THIS REPAIR. WHEN USING THE MDS2 AND THE DRB III; THE SYSTEM MUST BE OPERATING AT CIS CD 2047 OR HIGHER.
REPAIR PROCEDURE:
1. Log onto the MDS2 system.
2. Connect the MDS2 (Mopar Diagnostic System) and DRB III (Scan Tool) to the vehicle and switch the ignition key to"ON".
3. Use the arrow keys and select # 2 CONNECT TO MDS2 on the DRB III MAIN MENU SCREEN.
4. Use the arrow keys and select # 2 RUN MDS2 APPLICATION on the DRB III MAIN MENU SCREEN.
NOTE:
ONCE MDS2, DRB III, AND VEHICLE COMMUNICATION HAS BEEN ESTABLISHED, THE "CANNOT READ VIN FROM DRB III "MESSAGE (ON THE MDS) WILL BE REPLACED BY THE VEHICLE VIN. PRESS THE "OK"BUTTON ON THE MDS2 TO REQUEST A MDS2 SESSION FOR THE VEHICLE VIN INDICATED. PRESS THE "0K" BUTTON WHEN ASKED TO BEGIN SESSION.
5. Push the FLASH tab on the MDS2.
NOTE:
A MESSAGE MAY APPEAR THAT INDICATES NO UPDATES ARE AVAILABLE. IF THIS OCCURS, MAKE SURE YOUR DIAGNOSTIC EQUIPMENT IS OPERATING AT THE LATEST SOFTWARE LEVEL AS LISTED EARLIER IN THIS BULLETIN. IF THE LATEST SOFTWARE IS INSTALLED, AND NO UPDATES ARE AVAILABLE, ANOTHER VEHICLE CONDITION EXISTS THAT WILL REQUIRE FURTHER INVESTIGATION.
6. Select READ PART NUMBERS FROM VEHICLE and click SHOW UPDATES on the MDS2.
NOTE:
A MESSAGE MAY APPEAR THAT INDICATES NO UPDATES ARE AVAILABLE. IF THIS OCCURS, MAKE SURE YOUR DIAGNOSTIC EQUIPMENT IS OPERATING AT THE LATEST SOFTWARE LEVEL AS LISTED EARLIER IN THIS BULLETIN. IF THE LATEST SOFTWARE IS INSTALLED, AND NO UPDATES ARE AVAILABLE, ANOTHER VEHICLE CONDITION EXISTS THAT WILL REQUIRE FURTHER INVESTIGATION.
7. Select the new software part number with the light pen and click update controller software.
8. The MDS2 and DRB III will prompt for any operator action needed during the remainder of the reprogramming process.
NOTE:
DUE TO THE PCM FLASH PROCEDURE, A DTC MAY BE SET IN OTHER MODULES (EATX, BCM, MIC, SKIM) WITHIN THE VEHICLE IF SO EQUIPPED. SOME MAY CAUSE THE MIL TO ILLUMINATE. ALL DTC'S RELATE TO A LOSS OF COMMUNICATIONS WITH THE MODULE THAT IS BEING FLASHED. CHECK ALL MODULES, RECORD THE FAULTS, AND ERASE THESE FAULTS PRIOR TO RETURNING THE VEHICLE TO THE CUSTOMER. ERASE ANY FAULTS IN THE PCM ONLY AFTER ALL OTHER MODULES HAVE HAD THEIR FAULTS ERASED.
NOTE:
THE FOLLOWING STEPS ARE REQUIRED BY LAW
Fig. 1:
9. Type the necessary information on the "Authorized Software Update Label" p/n 04669020 (Figure 1). Attach the label to the JTEC PCM and cover the label with the clear plastic overlay.
Fig. 2:
10. Type the necessary information on the "Authorized Modification Label" p/n 04275086 and attach the label near the VECI label (Figure 2).
POLICY:
Reimbursable within the provisions of the warranty.
TIME ALLOWANCE:
Labor Operation No: 08-19-43-97 0.5 Hrs.
FAILURE CODE: FM - Flash Module