08 Nightrain Speedometer Comms

[Gooney_Bird]

Hey guys,

I was wondering if someone could tell me how the speedometer communicates with the engine control module on a 2008 Nightrain?

Is this a CAN based signal?

Thanks for any help.

 

[90FXRS]

If I remember correctly it's an SAE J1850 VPW (Delphi) Serial Bus.

The sensor signal goes to the ECM and it will encode the information onto the bus network. The speedometer simply plugs into the bus and decodes the information it needs to work. Same for the tachometer. The bus network contains a lot of information and everything on it gets what it needs to function properly.

If you're going to change to an aftermarket you might be re-wiring or adapting something.