RAM 1500 Van V8-5.2L CNG VIN T (1999)
PROM - Programmable Read Only Memory: Customer Interest
PCM - False MIL, And DTC P0740
NUMBER: 18-19-99
GROUP: Vehicle Performance
EFFECTIVE DATE: Aug. 20, 1999
SUBJECT:
Erroneous Mil Due To DTC P0740 - Torque Converter Clutch, No RPM Drop At Lockup
OVERVIEW:
This bulletin involves selectively erasing and reprogramming the JTEC Powertrain Control Module (PCM) with new software (calibration change
99Cal17).
MODELS:
1999 (AB) Ram Van
NOTE:
THIS INFORMATION APPLIES TO VEHICLES EQUIPPED WITH A 5.2L CNG OR LPG ENGINE AND A 46RE AUTOMATIC
TRANSMISSION.
SYMPTOM/CONDITION:
Some vehicles may exhibit a MIL illumination due to DTC P0740 - TORQUE CONVERTER CLUTCH, NO RPM DROP AT LOCKUP. The vehicle
operator will normally experience no other transmission problem.
The new software improves the monitoring of the known hydraulic pressure variations in the 46RE transmission.
DIAGNOSIS:
Using the Mopar Diagnostic System (MDS2) and or the Diagnostic Scan Tool (DRB Ill®) 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 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
CH6OOO
Scan Tool (DRB III(R))
1
CH7035
General Purpose Interface Bus Cable (GPIB)
1
CH7OOO/7001
J1962 Cable
1
MDS2
NOTE:
THE MDS2 AND DRB III(R) ARE REQUIRED TO PERFORM PART OF THIS REPAIR. WHEN USING THE MDS2 AND THE DRB III(R)
THE SYSTEM MUST BE OPERATING AT CIS CD 2039 OR HIGHER.
REPAIR PROCEDURE:
1.
Log onto the MDS2 system.
2.
Connect the MDS2 (Mopar Diagnostic System) and DRB III(R) (Scan Tool) to the vehicle and switch the ignition key to "ON".
3.
Use the arrow keys and select # 2 CONNECT TO MDS1 OR MDS2 on the DRB III(R) MAIN MENU SCREEN.
4.
Use the arrow keys and select # 2 RUN MDS2 APPLICATION on the DRB III(R) MAIN MENU SCREEN.
