OBD OnBoard Diagnostic System Generation

In April 1985, the California Air Resources Board (CARB) approved On-Board Diagnostic system regulations, referred to as OBD. These regulations, which apply to almost all 1988 and newer cars and light trucks marketed in the State of California, require that the engine control module (ECM) monitor critical emission related components for proper operation and illuminate a malfunction indicator lamp (MIL) on the instrument panel when a malfunction is detected. The OBD system also provides for a system of Diagnostic Trouble Codes (DTC) and fault isolation logic charts in the repair manual, to assist technicians in determining the likely cause of engine control and emissions system malfunctions. The basic objectives of this regulation are twofold:

• To improve in-use emissions compliance by alerting the vehicle operator when a malfunction exists.

• To aid automobile repair technicians in identifying and repairing malfunctioning circuits in the emissions control system.

OBD self diagnosis applies to systems which are considered to be most likely to cause a significant increase in exhaust emissions if a malfunction occurs. Most notably, this includes:

• All major engine sensors

• The fuel metering system

• Exhaust gas recirculation (EGR) function

Toyota Engine Diagnostic Receipt
Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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  • olivia
    Does 2015 RAV4 have onboard diagnostic system?
    4 years ago
    Where is the Onboard Diagnostic 2015 toyota corolla?
    3 years ago
  • pupetta
    Does Toyota Avalon 2006 have onboard diagnostics port?
    3 years ago
  • Alana
    Does 2012 toyota corolla have an onboard diagnostics system?
    2 years ago
  • edgardo
    How many obd port does a 2015 toyota corolla has?
    2 years ago
  • Bonnie
    How does onboard diagnostic system works?
    2 years ago
  • Mairi Sutherland
    What is the on board diagnostic system un a sienna?
    2 years ago
  • merimac
    Does my 2000 Avalon Toyota have an on board diagnostics port?
    8 months ago
  • Claudia
    What is toyota onboard diagnostic devices?
    6 months ago
  • joseph
    Does 2014 toyota require a special cable for full system diagnostics?
    4 months ago
  • arsi hatakka
    Does RAV4 2019 have diagnostic OBD Port?
    3 months ago

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