2002 5.3 OBD protocol?

[M123]

Hi.

What protocol do the OBD for the 2002 5.3 engine T go under?
Did find VPN and j1850 vpw but what's right?

Thanks

 

[George B]

@TJ Baker

 

[TJ Baker]

Hi.

What protocol do the OBD for the 2002 5.3 engine T go under?
Did find VPN and j1850 vpw but what's right?

Thanks

My guess is the SAE J1850 VPW protocol. That what GM was using mostly at the time. My 2005 5.3 LM7 Yukon uses J1850 exclusively.

Edit: I cannot say what was used for vehicles not sold in the USA. European models might be different?

 

[TJ Baker]

You could look at your OBD2 port and see what terminals have wiring in them. If it is SAE J1850 VPW it will have wires at terminals #2, #4, #5, and #16. Google "OBD2 Pinout" to find a diagram of what wires are used for each of the possible protocols.

 

[M123]

Thanks.
I don't know if they did modifie anything regarding diagnostic, shouldn't make any sense if we did get a other system.

If I look at my port so do I also have 14 activated but don't know if it's in use.

I have OBD scanner that cover j1850 vpw but it doesn't pick up any data from the port. The port have 12V so the regular problem that people have isn't the case here.

Can it be that the 02 did have VPN and with all other upgrades that did come 03 j1850 vpw was implemented to the Tahoe?
I can't sadly find ether tool or the design of the port layout on the VPN so are kinda uphill at the moment.

 

[M123]

Hmmm slot 14 are can low and was used from 2002 according to this page https://www.evoscan.com/technical-vehicle-manuals/104 and this figurations are GM-LAN.

So my guess my truck goes under protocol GM-LAN and are a previous version of canbus.
Now I am really curious what data you can send in that slot and why my truck have this figuration?

 

[TJ Baker]

have OBD scanner that cover j1850 vpw but it doesn't pick up any data from the port. The port have 12V so the regular problem that people have isn't the case here.

Exactly what model and manufacturer of scanner are you using?

 

[M123]

A no name reader that sells from a parts store here that they did put their own name on.

Did buy me Bluetooth OBDII connector, did pick up data from the j1850 vpw protocol via my phone, did try swapping between the can protocoles but didn't pick up anything, still a mystery what port 14 are used for.