PCM - Engine No Start Condition: Overview
NUMBER: 18-13-99GROUP: Vehicle Performance
DATE: June 18, 1999
SUBJECT:
Engine No-Start
OVERVIEW:
This bulletin involves selectively erasing and reprogramming the JTEC Powertrain Control Module (PCM) (calibration change 99CaI18).
MODELS:
1999 (WJ) Grand Cherokee
NOTE:
THIS INFORMATION APPLIES TO VEHICLES BUILT BEFORE APRIL 27, 1999 (MDH 0427XX) AND NOT EQUIPPED WITH THE SENTRY KEY IMMOBILIZER (SKIM) SYSTEM.
SYMPTOM/CONDITION:
An engine no-start or an engine crank-start-die condition may exist with vehicles not equipped with SKIM. Diagnostic Trouble Codes P1685 "SKIM Invalid Key" and/or P1686 "No SKIM BUS Messages Received" may be present in the PCM.
This condition may be due to erroneously learning of SKIM by the PCM. In most cases, the vehicle will start once the vehicle battery has been disconnected to reset the PCM.
DIAGNOSIS:
Using the Mopar Diagnostic System (MDS/MDS2) and or the Diagnostic Scan Tool (DRB III(R)) 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 CH6OOO Scan Tool (DRB Ill�)
1 CH7035 General Purpose Interface Bus Cable (GPIB)
1 CH7OOO/7001 J1962 Cable
1 MDS1 or MDS2
NOTE:
THE MDS1IMDS2 AND DRB Ill� ARE REQUIRED TO PERFORM PART OF THIS REPAIR. IF USING THE MDS1 AND DRB Ill� THE MDS MUST BE OPERATING AT RELEASE 21 OR HIGHER AND TIL CD RELEASE 1186 OR HIGHER MUST BE INSTALLED. IF USING THE MDS2 AND THE DRB III(R) THE SYSTEM MUST BE OPERATING AT CIS CD2035 OR HIGHER.
POLICY: Reimbursable within the provisions of the warranty.
TIME ALLOWANCE:
Labor Operation No: OB-19-43-91 0.5 Hrs.
FAILURE CODE: FM - Flash Module