How To Check If OBD Is Ready?

After 1996, the OBD2 integration became mandatory for all cars manufactured in the United States.

With the OBD2 system, your vehicle performs eleven diagnostic checks for various components such as fuel economy, transmission system, emission system, vehicle speed/idling control, engine misfire, etc.

All these diagnostics are performed by sensors attached to the various parts of your vehicle.

The data is processed by a computer called ECU (engine control unit) and displayed on a monitor. This monitor is also called the readiness monitor. It shows the emission health of your car.

How To Check If OBD2 Is Ready?

OBD2 scanning

If you’re using a Bluetooth OBD2 scanner to diagnose your car health then follow these instructions to ensure that your OBD2 is ready to read engine faults.

  1. Turn OFF your car engine.
  2. Plug an OBD2 scan tool into the OBD port.
  3. Turn ON the ignition key.
  4. Go to your smartphone’s Bluetooth settings.
  5. Connect with the OBDII device.
  6. Launch an OBD2 app on your phone.
  7. Wait for a few seconds until it scans the vehicle’s details.
  8. Check if your car details such as manufacturer, model, etc. are correct.
  9. Turn ON and accelerate the engine for 30 seconds.
  10. Check if live data such as engine rpm, engine temperature, fuel economy, etc. are fluctuating.

If you see all the live data are fluctuating when you accelerate the car, it means your OBD2 is ready to diagnose. Now, you can scan the error code with the help of the OBD tool.

How To Check Readiness Monitor?

If you’re going for an emission test, check if your vehicle is ready to pass the emission test or not.

Follow these steps to check if your car is ready for an emission test:

  1. Turn ON the ignition switch without starting the engine and wait for 15 to 20 seconds.
  2. Now monitor your engine check light or MIL (malfunction indicator lamp).

Newer Ford, Lincoln, and Mercury vehicles:

  • If MIL or Check Engine Light blinks eight (8) times then the monitor is “Not Ready”.
  • If MIL or Check Engine Light doesn’t blink and keep solid then your monitor is “Ready”.

Jeep, Chrysler, and Dodge vehicles:

  • If MIL or Check Engine Light blinks ten (10) times then the monitor is “Not Ready”.
  • If MIL or Check Engine Light doesn’t blink and keep solid then your monitor is “Ready”.

Honda and Acura vehicles:

  • If MIL or Check Engine Light blinks five (5) times then the monitor is “Not Ready”.
  • If MIL or Check Engine Light doesn’t blink and goes off then your monitor is “Ready”.

How To Pass OBD II Emission Test?

Every state has its own pollution norms. In order to drive your car without any issue, you should pass the emission test every year.

If you’re going for an emission test, follow these tips to pass OBD2 the test.

1. Make Sure Check Engine Light Is Off

Your car will not pass the emission test (also called the smog test) if the “Check Engine” light is glowing.

If your light is glowing, scan your ECU with an OBD2 scanner and find out the issue.

2. Clear Your OBD Codes

Before taking your vehicle for an emission test, clear your OBD codes. You can use an OBD2 scanner to clear the diagnostic code.

If you do not have an OBD2 scanner, follow these steps to clear OBD codes without a scan tool.

3. Check Your Monitor Readiness

Before taking your car for a smog test, you should check your monitor readiness.

You can use OBDLink or any Bluetooth OBD2 scanner to find out monitor readiness.

Conclusion

If your OBD2 scanner is connected, turn on the ignition and start the engine. If RPM and throttle temperature are fluctuating it means your OBD2 is ready to use. Always scan and clear the fault code before taking your car for an emission test.

Hi, I'm Richard, an ASE-certified mechanic in Florida, USA. I love to optimize car ECU for better fuel economy and troubleshoot engine code errors and fix them.

1 thought on “How To Check If OBD Is Ready?”

  1. Richard, I found your information very helpful with American made car Honda and Toyota.
    What about German cars like Mercedes BMW VW’s etc,.

    Reply

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