Any one know the knock retard PID ?

[forcefedjunkie]

If I have to explain what I mean you probably don't know the answer. Basically it's the parameter identification sent to the PCM to obtain knock retard from the diagnostic port. I'm trying to create my own scan tool software. Thanks!

Todd

[Shel-Game]

Which ECU? Here's a spreadsheet I made a while back showing all of the hex codes for the different DRB Functions built into the SBEC...

On the SBEC (I would assume the SMEC is the same codes, but I haven't looked to know for sure), you send a #14 followed by a #16, #17, #18, or #19 (for cyls 1-4) to get the retard value.

[forcefedjunkie]

Quote:

Originally Posted by Shel-Game Which ECU? Here's a spreadsheet I made a while back showing all of the hex codes for the different DRB Functions built into the SBEC... On the SBEC (I would assume the SMEC is the same codes, but I haven't looked to know for sure), you send a #14 followed by a #16, #17, #18, or #19 (for cyls 1-4) to get the retard value.

So "14" is the service, and "16", "17", "18", "19" are the PID's? Do you also have a spreadsheet of PID's? Thanks for the info!

[Shel-Game]

The entire DRB routine hex codes are in the spreadsheet I just posted. If you want to get into any mode (and there are modes in the SBEC that are not supported by the DRB! - must've been a factory only tool available to get to some of them), it's in that spreadsheet. I made that from my dis-assembly of the T1 SBEC, but the T3 and TIV use the same codes. The V6 is almost the same.

You have to expand the "+" symbols at the left to see all the codes. I tried to setup a hierarcy in the Excel sheet and it just didn't work too well. If you expand everything, it's more clear.

[forcefedjunkie]

Gotcha!

[forcefedjunkie]

Rob, one more question. Do happen to have the conversions for the codes to engineering units, i.e., converting a returned hex value to real units? Thanks, this info. has been very helpful.

Todd

[Shel-Game]

Most of them.

Coolant temp is scaled from -60 to 259F
MAP is scaled from -14.7 to +14.7 psi (if the car has a stock 2-bar MAP sensor)
Fuel PW is scaled from 0 - 49152ms

That's all I can remember off the top of my head. What others did you want the scale for?

[forcefedjunkie]

Knock retard would be the other of interest. Thanks!

Todd

[Shel-Game]

There's knock volts, and knock retard degrees. The volts variable is scaled 0-5V, the retard degrees are scaled 0 - 128 deg, I think.

I say "I think" because I'm 99% sure the retard value is unsigned. If the value looks wacky using that scale, then it must be a signed value and the scale would be +/- 64 deg instead...