2LZ

After our last day excursion with the '96 LT1, I popped a CEL prior to getting home. Car still ran fine. Just so happened, I had a Super Coupon to the OBD2 tester at Harbor Freight so I snagged it. I know...I know... HFT is not the best stuff but I don't use my tools for a living and I've had good luck the three times a year I need them.

So, unwrap the tester, plug it in, turn on key. Nothing. Recheck the plug, fiddle, re-plug, etc... No go. Crap, bad tester out of box. Oh well. It's HFT. What did I expect?
Just for grins, I walked out to my '97 K1500, plug it in and VIOLA! It lit right up. I ran through the simple menu's, cleared it all and unplugged it. Worked great.

Back to '96 Corvette. Plug it in. No go.
After digging out the "war and peace" version of the FSM (parts 1 and 2) and nosing around to try to locate the unusual and obscure technique of simply reading and clearing codes, i threw in the towel and disconnected the battery for a while. Reconnected. No CEL. Drive it around a while and it never came back on.

Anyone have any idea why it won't light the code reader? It's supposed to work '96 and newer.

billschroeder5842

Go to Auto Zone and ask them to pop on their reader. If the AZ one works you know your answer.

pcolt94

The 96 was the first year of OBD2 and things were not fully up to speed. On most modern cars the 12 volts power was built into the connector for the scanner. I believe for the 96 corvette the power for the scanner was not supplied by the ALDL connector back then, but external power was used to run the scanner.

My Tech 1 which was made mainly for OBD1 requires external power from the cigarette lighter. Eventually the software for OBD2 was released and the adaptor cables for OBD2 however it still uses external power which was by design back then. That’s how the dealers did it with the factory tool.

Probably a little later on the car makers and test equipment makers added the pin in the ALDL connector for power which was probably in the standards they were going to built to.

Hershey71

Because it's a Harbor Freight OBDII reader crazy: :. The one I had wouldn't work either so I ended up paying 3 times the price of the Harbor Freight and have one that's 100 times better. It's an AUTEL MX808 and will read every sensor and module in the car. It's also a small 7" tablet and is very versatile best money I ever spent for a diagnostic tool

MatthewMiller

The little bluetooth and wifi readers that plug in to the port and send the info to your phone will work in a 96. I'm not sure if they'll give all the info you seek, but they will read codes and can log some data while driving.

2LZ

Success! I finally pulled and tested every fuse in the little panel on the passenger side dash.
For those who want to know, as opposed to all the You Tube vids for most cars that say the power to the OBD2 connector usually runs off the "cigar" fuse, on a 1996 C4, the OBD2 connector is powered by Fuse #36 "RH CTSY".
In short, if your door courtesy lights are out, your OBD2 connector won't work either.