question about obd2 code reader

[Spykem4e]

Hi guys,

I have a scan tool, Innova 3100 CAN and obd2 code reader, and its working fine as far as I know but I have a question regarding the green light, the yellow light and the red one.

When I plugged the obd2 code reader in my car for the first time, 3 years ago, no code showed up (no check engine light either) and I had the green light showing on the code reader. 2 years ago, I had my first check engine light on the dashboard so I scanned my car and I had the P0420 (bad cat bank 2) + red light. So I changed the catalytic converter and erased the code. I then scanned the car and the results were no code + yellow light (not ready for an emission test).

So since last year, every time I try to scan my car, I have no code showing + yellow light.

How come I can't have a green light since everything is working perfectly?

Also, in the future (for Christmas), I wanna get myself a new scanner that can read live data, that can read also abs code etc. What would be your suggestion?

-Mark.

 

[GMBoy]

You are correct on how the lights work. You should have a green light by now so there is 1 (or more) OBD2 readiness tests that have not completed. Have you performed a "drive cycle"? Each manufacturer has a specific drive cycle (basically how you should drive the car in a set # of miles). But, in any event, after about 25-50 miles of driving ANY car should have run all its OBD2 on board tests so you either have an issue with the tool or the car never gets driven a certain way for the PCM/ECM to run a certain test - which leaves on the yellow light.

As for more advanced tools that can read live data - Innova makes some nice ones that are priced reasonably.

 

[sciphi]

It's possible you have a solitary test not run. I had that happen when my battery died 2 days before my inspection appointment (New York registration) this past winter. Everything else ran but that one test, and the car passed inspection. Down here you're allowed 2 emissions tests to not be run by federal law. Not sure what the laws for you are.

 

[Gary Allan]

If you happened to check the car with the gas tank too full or too empty, the EVAPURGE may not even operate. It varies by man, but that's why they allow 1 or 2 readiness states to be incomplete. I had to play to get my son's Cherokee to PASS. It would have gone through fine, but the tank was full. No EVAPURGE. He had a failed pre-cat so I had to get it in the window of no CEL ..but the heater circuit being the only incomplete state.

 

[Spykem4e]

thanks a lot guys!

I've searched through the internet how to make an obd2 drive cycle + a gm drive cycle. I found it.

This morning, I did the step by step instruction and after that, I plugged the scanner and guess what, no code + GREEN light! yippi!!!

Tks a lot, I've learned something else today! Tks to you guys!

 

[Gary Allan]

You've gotta love the information age

 

[Spykem4e]

Originally Posted By: Gary Allan
You've gotta love the information age

oh yeah!

+ I did a little MAF sensor cleaning + throttle body cleaning today. You can see my post in the mechanical section:

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1566198#Post1566198

I don't know if you remember that you gave me your email so we could try to diagnose the surging problem I had with the 5l40e transmission on my CTS but read the post and the problem is solved

 

[Gary Allan]

It's a great feeling to have solve a puzzle.