Can vehicle speed be read through the diagnostic port on logic module cars? A smog referee told my friend that there was no speed shown but no 15 code is present. Is this normal?
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Can vehicle speed be read through the diagnostic port on logic module cars? A smog referee told my friend that there was no speed shown but no 15 code is present. Is this normal?
If you can, that would be news to me.
You can. But, there's no special test code for it (I don't think). You have to get it in logging mode. I don't know if all the scan tools support it (DRB-I certainly would).
My OTC 2k shows it.
Yeah, I agree with a scan tool but the way I read it last night, could be tired, lol, was that the smog guys are saying you can by just using the test port, no scanner.
I wasn't there but I think it's a pretty safe guess that a scanner was used. Could the computer (ND) possibly have the speed function disabled, for whatever reason?
Possible, but not likely. What computer/year is it?
'87 T2 logic module (in an L-body). Is there perhaps a different pin that should lead to the to the diagnostic port?
No, it's a serial interface. If they get anything through the port, they should get it all.
'87 T2 LM - is that what they're using to setup the scanner? If they use the wrong engine VIN code, it could give the wrong data.
I figured it out. We are using a non L-body computer with L-body wiring. The speed sensor wire was going to the wrong pin on the module. Once I changed that everything was good!:amen: