can't connect to my ob2 when my tccm is connected

 

The TCCM may be corrupting the class 2 data lines which is how the scanner interfaces with the VCM and reads engine data. Do any other problems clear up? Are you having 4wd issues?

What year is the vehicle?

George

 

yes its a 2000 chevy blazer off and on

 

You are a man of few words. I am assuming you mean that you have 4wd problems but I don't know if your telling me if you have other problems with other modules.

That said, Something is wrong with the TCCM, its wiring, connectors, power or ground. If your a parts swapper get another TCCM or have your refurbished. If you are like me and don't like potentially wasting money and want a diagnosis first so you know what to fix or replace then test first:

1) Quality of the power and ground to the module
2) Inspect connectors for fit and corrosion
3) Inspect the wiring
4) Isolate and test the class 2 wire from the TCCM to the blade connector near the DLC
5) I am sure that you don't have a GM Tech 2 scanner to diagnose your TCCM so if all good, have a module rebuild house test your TCCM or replace it

Let me know if you need help with any of this.

George

 

check cigarette lighter fuse