Hello, I am new, I read this thread here P0650 indicator lamp (MIL) control circuit malfunction about the P0650 code and it helps a lot. I Recently purchased a 2012 chevy express van 4.8 2500 71k. Not passing emissions. The CEL does not illuminate on starting whereas other warning lights do. So maybe the bulb is burned out, loose wiring, fuse etc. The dmv smog test shows the following code:1) P0650-malfunfunction indicator lamp short circuit. If someone could tell me which nr fuse controls the MIL or better known as the check engine light on my van it would be a start. With my luck lately, the fuse is unlikely to be it but it still is the first thing to check. I checked for nr 48 fuse but that is for a relay on my vehicle.
Thank-you

I checked the fuses both sides, some had to be checked with key on. I was hoping to find the lighter/dlc fuse blown but it was good. I am concerned about a 40 amp fuse nr 45 labeled Engine control module/powertrain because the fuse is actually missing. Any reason for someone to pull this fuse? Could it be the reason my CEL does not illuminate? The van runs well, just need to figure out this fault code p0650.

 

My own experience with this code related to a burnt battery light LED on the dash cluster board soldered a new one back on and fixed it

 

What causes the P0650 code?
Several problems may cause a P0650 code including:

• Damaged, open, shorted, or corroded wiring and related electrical components in the CAN bus harness
• Damaged or loose control module ground strap wire
• Damaged or defective malfunction indicator lamp bulb or LED
• Damaged or defective malfunction indicator lamp circuit
• Damaged or defective CAN bus
• Damaged or defective PCM (rare)

 

Why would someone pull the 40 amp fuse nr 45 labeled Engine control module/powertrain, because the fuse is actually missing. Would this missing fuse disable the CEL light from illuminating? If the fuse is missing and it controls the malfunction indicator lamp circuit, the circuit would not complete itself, therefore no CEL light. Can anyone tell me if the missing ecm/powertrain fuse would cause this?

 

Well, the CEL is controlled by the PCM; and if the fuse your talking about provides the power for the PCM, then yes, that would probably disable the light.
However, if the PCM was powerless, the engine wouldn't run, wouldn't start, the transmission wouldn't shift, etc.

Edit:
If the PCM was without power, I doubt if there would be anyway for the P0650 to be generated, or stored, or read