frankrizz

Good Morning Members,
My 94 GM 4l60E recently showed a DTC 97. My speedo works fine
and I don't have any shifting issues. I checked the two wires going to the
switch and they look ok. I replaced the switch and still get the code. Can't
erase it with my 9495 scan. Any help is appreciated. Thanks

shoebox

What switch? If you meant the two wires to the VSS (sensor), then you are looking in the wrong place. Code 97 is for VSS OUTPUT, which is the signal from the PCM (B8) to the speedometer. I don't see a signature and I don't memorize every member's car, so I don't really know anything about your vehicle. If you have a swap, then the speedo might not be electrically compatible.

frankrizz

Thank you for your info.
This is a swap and I am using an Autometer Speedo. How do I know if this
is compatible with the PCM ? It works pretty accurately. Just throws the
code. Thanks, Frank

shoebox

I don't know what the electrical criteria is, but apparently the PCM is not satisfied with it, because the code is for improper voltage potential. Maybe Gary Doug would have an idea.

Injuneer

The codes sets when the PCM determines there is an incorrect voltage on circuit 817 for 26 seconds. Circuit 817 runs from the PCM to the speedo and the cruise control. If you are using a non-factory speedo, there's a good chance that is the problem.

The trouble-shooting for the circuit in factory manual page 8A-33-2 includes "Check for proper installation of aftermarket electronic equipment which may affect the integrity of other systems."

If you clear the code (pull PCM BAT fuse for 30-seconds), how fast does it come back?

frankrizz

Code comes back within 10 seconds. Waiting to hear from Autometer tech.
team today. I will keep you posted. Thanks, Frank

frankrizz

Spoke to Autometer tech. today. They are going to replace my unit with an
upgraded circuitry. Hopefully this will work. Thanks again for your feedback.