Fuel Gauge

[CaseyMx]

I have a 2011 GMC 2500HD Denali with 6.0 ltr. Filled up a while back and fuel gauge didn't go quite to full. Later on it dropped to E. I changed the sending unit in a rush situation and it still doesn't work. So I've decided to slow down and do a little troubleshooting. Read the codes and I have:

P0449 - evap vent valve malfunction.

P0452 - evap pressure sensor

P0461 - fuel level voltage signal

P0463 - innacurate fuel level reading

 

I am now wondering if I may have a connector issue being that the evap and level sending unit wiring is in the same harness under the truck and both of these issues happened at the same time. I don't want to left the bed or drop the tank just to test voltage. Does anyone know if there is a connector and where it may be between the computer and this harness? I would much rather troubleshoot voltage under the hood somewhere than on the connector on top of the tank.

[davester]

You might find your wiring info on https://www.gmupfitter.com/

 

You might also consider getting a subscription to the full-service manual for your truck at a site like alldatadiy.com

It includes wiring diagrams, connector pinouts, power and ground locations, harness routing, as well as diagnostic procedures.

[CaseyMx]

Wow! Didn't know something like this existed! Think the gmupfitter will help me.

Thanks a bunch!