Emissions - OBD-II I/M Program Summary
NO: TSB-03-17-005DATE: July, 2003
MODEL: All 1996-98 Models
SUBJECT:
SUMMARY OF OBD-II INFORMATION FOR
INSPECTION & MAINTENANCE (I/M) PROGRAMS
PURPOSE
This bulletin contains a summary of OBD-II information and certain vehicle conditions related to the Environment Protection Agency (EPA) Inspection & Maintenance (I/M) testing programs now being instituted in many states.
AFFECTED VEHICLES
All 1996-98 Models
SERVICE INFORMATION
Readiness Code Completion
Code Setting - For all 1996-98 model year Mitsubishi vehicles, all the required monitors (02 sensor, 02 sensor heater, EGR, catalyst, and purge flow monitor), except the enhanced (strict) evaporative system* monitor, must be completed on the first drive cycle, at which point the scan tool will display the monitors as "incomplete". On the next drive cycle, as each of the monitors complete, the scan tool will show the monitor as "complete". The readiness code for the enhanced evaporative system leak monitor will be set to "complete" upon completion of one cold start monitor cycle after all other required monitors have been completed.
This condition was based on a literal interpretation of the California OBD-II regulations. After consultation with the California Air Resources Board (CARB), this was changed for 1999 and subsequent model years to set the Readiness Code to "complete" the first time each individual monitor is completed.
The most stringent driving criteria for monitors to run are required for the catalyst monitor and the evaporative system leak monitor, in that order of difficulty. The evaporative system leak monitor is generally the last to be set to "complete" since it has a cold-start requirement.
Key-off Reset - For 1996 and 1997 models equipped with the V6 engine, turning the key off at the end of the drive on which the final Readiness Code is set to "complete" will result in resetting all Readiness Codes to "incomplete". If the vehicle has at least one Readiness Code as "incomplete", the other Readiness Codes will be retained at key-off. Once the Readiness Codes have all been completed once, this key-off reset will not require the two-cycle Readiness Code setting as described above. After key-off reset, each Readiness Code will be set to "complete" the next time each monitor is completed. When codes are cleared by scan tool or disconnecting the battery or the PCM, the two-cycle process will again be needed. This situation was due to a misunderstanding of the software specification, and has no emissions impact.
Fault Detection
Fault detection will occur without regard to the status of Readiness Codes. If a hard fault is detected for a two-drive fault, (e.g. initial detection and then confirmation), a temporary fault code will be set on the first monitor-enabled drive and then matured to a DTC (and the MIL will be turned on) during the second monitor-enabled drive. All Readiness Codes may-or-may-not be "complete" within those two drive cycles.
Reflashable OBD II Computers
For the 1996 and 1997 model years, none of the Mitsubishi-designed OBD-II computers are reflashable. The 1996 through 1998 Eclipse models with 2.0L non-turbo engines use a Chrysler-designed OBD-II computer that is reflashable. All subsequent models except the 1998 2.4L Galant are reflashable.
* Enhanced (strict) evaporative systems were phased in at 10/30/50/100% from 1995 - 1998 MYs. See TSB-03-13-005 "OBD-II Drive Cycle" dated May 2003 for 1996 and 1998 model year applications.