Craftsman 14063 manual OBD2 Monitors

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Onboard Diagnostics

OBD2 MONITORS

„If the conditions that caused the MIL to light are no longer present for the next three trips in a row, the computer automatically turns the MIL “Off” if no other emissions-related faults are present. However, the DTCs remain in the computer’s memory as a history code for 40 warm-up cycles (80 warm-up cycles for fuel and misfire faults). The DTCs are automatically erased if the fault that caused them to be set is not detected again during that period.

„Misfire and fuel system faults require three trips with “similar conditions” before the MIL is turned “Off.” These are trips where the engine load, RPM and temperature are similar to the conditions present when the fault was first found.

After the MIL has been turned off, DTCs and Freeze Frame data stay in the computer’s memory.

„Erasing the DTCs from the computer’s memory can also turn off the MIL. See ERASING DIAGNOSTIC TROUBLE CODES (DTCs) on page 28, before erasing codes from the computer’s memory. If a Diagnostic Tool or Scan Tool is used to erase the codes, Freeze Frame data will also be erased.

OBD2 MONITORS

To ensure the correct operation of the various emissions-related components and systems, a diagnostic program was developed and installed in the vehicle’s on-board computer. The program has several procedures and diagnostic strategies. Each procedure or diagnostic strategy is made to monitor the operation of, and run diagnostic tests on, a specific emissions-related component or system. These tests ensure the system is running correctly and is within the manufacturer’s specifications. On OBD2 systems, these procedures and diagnostic strategies are called “Monitors.”

Currently, fifteen Monitors are supported by OBD2 systems. Additional monitors may be added as a result of Government regulations as the OBD2 system grows and matures. Not all vehicles support all fifteen Monitors. Additionally, some Monitors are supported by “spark ignition” vehicles only, while others are supported by “compression ignition” vehicles only.

Monitor operation is either “Continuous” or “Non-Continuous,” depending on the specific monitor.

Continuous Monitors

Three of these Monitors are designed to constantly monitor their associated components and/or systems for proper operation. Continuous Monitors run constantly when the engine is running. The Continuous Monitors are:

Comprehensive Component Monitor (CCM)

Misfire Monitor

Fuel System Monitor

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Craftsman 14063

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Contents Page Table of Contents What is OBD? IntroductionYou Can Do It Easy To UseSafety Precautions Safety FirstVehicles Covered Data Link Connector DLC LocationAbout the Code Reader OBD CertifiedControls and Indicators Controls and IndicatorsDisplay Functions Display FunctionsAbout the Code Reader Onboard Diagnostics Computer Engine ControlsIntroduction of Electronic Engine Controls Basic Engine Computer Control System Typical Computer Control SystemOn-Board Diagnostics First Generation OBD1 On-Board Diagnostics Second Generation OBD2OBD2 Terminology Not all vehicles support all fifteen Monitors Diagnostic Trouble Codes DTCs 2 0 DTCs and MIL Status OBD2 Monitors OBD2 MonitorsNon-Continuous Monitors Onboard Diagnostics Onboard Diagnostics Onboard Diagnostics Onboard Diagnostics Onboard Diagnostics OBD2 Reference Table DTCName Monitor Preparation for Testing Before YOU BeginUsing the Code Reader Code Retrieval ProcedureLED Erasing Diagnostic Trouble Codes DTCs Using the Code Reader Hardware Requirements About RepairsolutionsAccessing RepairSolutions Minimum System Operating RequirementsUsing the Code Reader Vehicle Applications ABS Vehicle Applications Makes CoveredWarranty and Servicing Craftsman TWO Year Full WarrantyReplacement Parts
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