PCM - MIL ON/DTC 21 Set
NO: 18-12-95GROUP: Vehicle Performance
DATE: May 12,1995
SUBJECT:
Check Engine Light On, DTC 21, "Down Stream O2S Unable to Switch Rich/Lean"
MODELS:
1995 (JA) Stratus
NOTE:
THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH A 2.0L SOHC ENGINE AND MANUAL TRANSAXLE BUILT BEFORE MAY 5, 1995 (MDH 05-05-XX).
SYMPTOM/CONDITION:
Check Engine Light (MIL) is on, Diagnostic Trouble Code (DTC) 21, "Down Stream O2S Unable to Switch Rich/Lean" is set.
DIAGNOSIS:
Using the Mopar Diagnostic System (MDS) or the Scan Tool (DRBIII) and appropriate Diagnostic Procedure Manual, verify that all engine systems are functioning correctly. If Diagnostic Trouble Codes (DTC's) other than "Down Stream O2S Unable to Switch Rich/Lean" are present, record them on the repair order for future reference and repair as necessary.
EQUIPMENT/PARTS REQUIRED:
1 CH6000 Scan Tool (DRBIII)
1 CH7035 General Purpose Interface Bus Cable (GPIB)
1 CH7000 J1962 Cable
1 4669020 Label - Authorized Software Update
1 4275086 Label - Authorized Modification
REPAIR PROCEDURE:
This bulletin involves selectively erasing and reprogramming the Powertrain Control Module with new software (calibration change).
NOTE:
MDS AND DRBIII ARE REQUIRED TO PERFORM THE FOLLOWING REPAIR. MDS MUST BE OPERATING WITH RELEASE 16 OR HIGHER AND TIL CD 1079 OR HIGHER INSTALLED.
1. Connect the MDS (Mopar Diagnostic System) and DRBIII (Scan Tool) to the vehicle and power them up.
2. Use the arrow keys and select # 2 MDS DIAGNOSTICS on the DRBIII MAIN MENU Screen.
3. Use the arrow keys and select DIAGNOSTIC MENU on the MDS, then press NEXT MENU.
4. Use the arrow keys and select CONTROLLER PROGRAMMING on the MDS, then press NEXT MENU.
5. Use the arrow keys and select PROGRAM CONTROLLER PART on the MDS, then press NEXT MENU.
6. Follow the steps presented on the MDS and DRBIII which will allow the DRBIII to obtain the current part number of the controller.
7. The MDS will display the part number of the controller on the vehicle and the appropriate replacement part number, then press NEXT MENU to begin programming.
If the controller on the vehicle has already been updated or programmed, a NO UPDATES AVAILABLE message will be displayed. Check the part number of the controller on the vehicle and compare it to the part number displayed. If the controller has already been updated, then the DTC "Down Stream O2S Unable to Switch Rich/Lean" actually exists and should be corrected.
8. The MDS and DRBIII will prompt the operator for any action needed during the remainder of the programming process.
NOTE:
THE FOLLOWING STEPS ARE REQUIRED BY LAW.
9. Type the necessary information on the "Authorized Software Update" label, P/N 4669020. Attach the label to the PCM and cover the label with the clear plastic overlay.
10. Type the necessary information on the Authorized Modification Label and attach the label near the VECI Label.
POLICY: Reimbursable within the provisions of the warranty.
TIME ALLOWANCE:
Labor Operation No: 08-19-42-92 0.5 Hrs.
FAILURE CODE: FM - Flash Module