On-Board Diagnostics

  1. OBD I regulations went into effect on all 1980 model year vehicles in California
    False.  1988
  2. OBD I regulations went into effect on a Federal vehicles in 1996.
    False.  OBD II = 1996. OBD I = 1988
  3. A malfunction indicator lamp (MIL) is used to alert the driver of any computer related faults that have occured.
  4. Cylinder misfire monitoring requires measuring the firing voltage to the spark plugs.
  5. An OBD II system monitors the ability of the fuel tank pressure to hold pressure.
  6. Diagnostics monitoring on OBD I equipped vehicles includes all of the following except
    Engine misfire detection

    • Includes: 
    • fuel metering, major input sensors, egr system
  7. Which of the following systems is not monitored by the PCM?
    Fuel pressure

    • Monitored:
    • fuel trim, egr, evap
  8. OBD II guidelines state that manufacturers must used standard
    • Communication protocol
    • Diagnostic test connector
    • Acronyms
  9. OBD I systems use a minimum of _____ oxygen sensor(s)
  10. While the PCM is operating in closed loop, the fuel system monitoring checks
  11. An OBD II MIL will illuminate if vehicle emissions exceed _____ times the allowable standard for that model year.
  12. The catalyst efficiency monitor is being discussed.  Tech A says if the catalytic converter is not reducing emissions properly, the voltage frequency of the downstream HO2S will match the upstream O2s sensor voltage.  Tech B says if a fault occurs in the catalyst monitor system on 3 drive cycles, the MIL will illuminate.
    A only
  13. Which of the following is not related to an OBD II drive cycle?
    IM240 test

    initiates and completes a specific monitoring sequence, verifies a symptom, verifies repair
  14. OBD II is on all _____ and newer domestic passenger cars and light trucks.
  15. Technician A says it takes 3 consecutives good drive cycles to turn the MIL light off.  Tech B says it takes 40 consecutive drive cycles to purge codes from memory.
    A only.  B is warm-up cycles
  16. The _____ rule determines if an input signal to the PCM is within its normal range.
  17. Type B engine misfires are excessive if the misfiring exceeds 2% to 3% in a _____ rpm period.
  18. The _____ monitor checks for fuel system leaks and purge flow.
  19. The _____ sensor is used to monitor the operation of the AIR system.
  20. The fuel system monitor checks short-term and long-term fuel _____
Card Set
On-Board Diagnostics
On-Board Diagnostics