Is my Module Faulty

Question

Installed EVO ONE on a 2001 Chevrolet Suburban with NO T-harness. Plugged module per procedure, Blue light came on, Plugged in harnesses, released button, no red light came on. Tried several times, troubleshooting says J1850 serial data line not seen. Tested line with scan tool and functioning fine. Checked continuity from OBD connector to module connector - good. Confirmed conection from connector to module pin - good. Looking for input if module is faulty. Please advise.

Regards, Bob____

Answer 1

What is the 12 digit service number of the module?

What is the voltage on the j1850 line directly on the EVO vs the car?

 

note, sometimes straight out starting these cars instead of waiting for the red led after releasing on BLUE, helps with programming. Especially whent he data line rests at less than 1V.

Comments

Hello Robert T,

Thak you for your input!

S/N: 002B04 010010

When I tested the voltage at the J1850 line at the module connector it was fluctuating from 0v to ~ .900v when the vehicle is running, same reading at the OBSII connector. with the ignition off, I also ohmed the J1850 circuit from the OBDII connector to the module connector and had 0 ohms. I'm confident that circuit is good.

When we tried to program the module today, we get the LED's in the following sequence;

Blue, Yellow, Red, Red/Blue, starting over with Blue, Yellow, Red, Red/Blue, starting over with Blue and so on. I released the program button when the Blue light was on alone - as the programming directions indicated. Released the button and inserted all other connectors. When I turn the ignition on, the blue LED goes out, Red LED sequence never happens. When I turn the ignition off, the blue LED comes back on.... re-confirmed all input circuits to the module are good. I'm at a loss other than thinking the module is suspect.

      Regards, Bob______

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Robert,

    I failed to add that I did try starting the vehicle rather than waiting for the red LEDwhen programming and that made no difference. When I shut the vehicle off, the blue LED came back on.

    Reagrds, Bob_____