Recently purchased a 2012 chevy express van 4.8 2500 71k. Not passing emissions. The CEL does not illuminate on starting whereas all the other warning lights do. So maybe the bulb is burned out, loose wiring, fuse etc. The dmv smog test shows the following codes:1) P0650-malfunfunction indicator lamp short circuit 2) HO2s 12 heater resistance P0054 3) P0496 evaporative emission system high purge flow.

In the test results it shows FAIL under the READINESS section, everything else passed. It also shows the following tests as not complete: 1) EVAP CONTROL 2) O2 SENSOR. I have read some stuff about “drive cycles” and “readiness monitors” and it gets a little complicated for the average car owner, like say someone with little technical knowledge. I was not aware that these things could affect your smog test.

I have experience with obd11 scanners and auto repair. But the last vehicle I worked with was about 15 years older than my van. I plan on keeping the van so to start out I will need a decent obd11 scanner and a set of GM shop manuals.

My questions are: 1) any ideas on the CEL 2) any ideas on the DTC’S showing up 3) How can I pass emissions?

Thank-you