GM PIDs

[ColPaul]

How are the values for 1192 interpreted? The tables shows that it returns 1 byte, but the description says that it ranges from 0-3200. Maybe a 12.5 times the byte value?

[Tom H]

How are the values for 1192 interpreted? The tables shows that it returns 1 byte, but the description says that it ranges from 0-3200. Maybe a 12.5 times the byte value?

It's been a long time since I looked at this... The value for PID1192 is returned in a single byte from location $013A in the TSide internal RAM. I believe it is tested against rpm/12.5 as you suggest. Here is a snip o code I found from some earlier work...

52A1  B6 01 64        LDAA   $0164        ; RPM/12.5 AVERAGE
52A4  B1 01 3A        CMPA   $013A        ; TARGET IDLE RPM: RANGE 0-3200
52A7  22 05           BHI    $52AE        ; BRANCH IDLE ABOVE TARGET

52A9  20 18           BRA    $52C3        ; IDLE <= TARGET

-Tom

[ColPaul]

Tom, Thank you! Not sure what my dad's truck is doing with respect to desired idle vs. actual so this will be extremely helpful. It's on a 2005 P59 PCM, but I am hoping that the protocol/enhanced PID is the same.

Paul

[Tom H]

Tom, Thank you! Not sure what my dad's truck is doing with respect to desired idle vs. actual so this will be extremely helpful. It's on a 2005 P59 PCM, but I am hoping that the protocol/enhanced PID is the same.

Paul

Hi Paul,

Interested to hear how this works out. I expect GM will keep the definition across generations.

-Tom