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OBD II - Improper MIL Illumination: Overview

NO: 18-10-98

GROUP: Vehicle Performance

DATE: Feb. 27, 1998

SUBJECT:
OBD II Misfire Indicator

THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 18-26-97 REV. A, DATED SEP. 5, 1997 THAT SHOULD BE REMOVED FROM YOUR FILES AND NOTED IN THE 1997 TECHNICAL SERVICE BULLETIN MANUAL (P/N 81-699-98004). ALL REVISIONS ARE HIGHLIGHTED WITH **ASTERISKS** AND INCLUDE THE ADDITION OF 1997 AN MODELS.

MODELS:
**1997**-1998 (AN) Dakota
1998 (BR/BE) Ram Truck

NOTE:
THIS BULLETIN APPLIES TO 1998 MODELS BUILT BEFORE AND INCLUDING THE FOLLOWING DATES:

11TH POSITION OF VIN G (SALTILLO), J (ST LOUIS), M (LAGO) AUG. 20, 1997 (MDH 0820XX) - S (DODGE CITY) AUG. 19, 1997 (MDH 0819XX) AND **ALL 1997 AN MODELS**.

This information applies to all gasoline equipped models except heavy duty emission 5.9L federal and heavy duty emission 8.0L federal packages. The VECI label can be inspected to see if the 5.9L or 8.0L applies to this action. The VECI code sequence for these heavy duty emission models will be WCRXH08.0BA1 for 8.0L and WCRXH05.9BA1 for 5.9L. The highlighted H designates heavy duty. The location of the label for 5.9L is on the air cleaner and 8.0L on the air pump bracket. No diesel vehicles apply to this action.

DISCUSSION:
**The above model trucks with gasoline engines will not illuminate the MIL properly when misfire is detected. The software within the powertrain control module has been revised to correct an OBD II system monitor that is non-compliant based on misfire requirements set forth by the Federal Government and C.A.R.B.. **

**NOTE:
ALL APPLICABLE VEHICLES BROUGHT IN FOR ANY MAINTENANCE MUST HAVE THIS REFLASH PROCEDURE PERFORMED.**

EQUIPMENT/PARTS REQUIRED:

1 CH6000 Scan Tool (DRB III)
1 CH7035 General Purpose Interface Bus Cable (GPIB)
1 CH7000/7001 J1962 Cable
1 04669020 Label - Authorized Software Update
1 04275086 Label - Authorized Modification

NOTE:
THE MDS AND DRB III ARE REQUIRED TO PERFORM THIS REPAIR AND THE SYSTEM MUST BE OPERATING WITH RELEASE 21 OR HIGHER AND TIL CD RELEASE 1152 OR HIGHER MUST BE INSTALLED.

POLICY:
Reimbursable within the provisions of the warranty.

TIME ALLOWANCE:

Labor Operation No: 08-19-49-98 0.5 Hrs.

FAILURE CODE: FM - Flash Module